Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/01/15
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
945 AM MST THU JUL 30 2015
.SYNOPSIS...
HIGH PRESSURE BUILDING OVER THE REGION WILL GRADUALLY REDUCE RAIN
CHANCES TODAY ONWARD INTO THE UPCOMING WEEKEND...AND INTO EARLY NEXT
WEEK WITH AT LEAST SLIGHT CHANCES TO REMAIN OVER SOUTH-CENTRAL
ARIZONA. TEMPERATURES WILL TAKE A SLIGHT DIP BELOW NORMAL TODAY DUE
TO WIDESPREAD CLOUD COVERAGE...BEFORE A SLOW WARMING TREND FRIDAY
INTO EARLY NEXT WEEK AS THE ATMOSPHERE SLOWLY DRIES OUT.
&&
.DISCUSSION...
MORE SUNSHINE TODAY THAN YESTERDAY BUT MOST OF THE 12Z SOUNDINGS
OVER ARIZONA SHOW LESS MOISTURE COMBINED WITH SOMEWHAT WARMER
TEMPERATURES ALOFT. THIS RESULTS IN EVEN LESS CAPE THAN YESTERDAY.
LATEST MODELS REFLECT THIS TO VARYING DEGREES SHOWING MUCH OF CENTRAL
AND EASTERN ARIZONA WITH RELATIVELY SPOTTY CAPE DISTRIBUTION. FURTHER
WEST...THE MOISTURE IS BETTER AND MODEL CAPE IS BETTER AS
WELL...THOUGH NOT TREMENDOUSLY. IN GENERAL...NAM IS QUITE A BIT MORE
GENEROUS THAN GFS WITH RAP IN BETWEEN. NAM LOOKS OVERDONE FOR THE
LOWER COLORADO RIVER VALLEY. WHERE THERE DOES SEEM TO BE SOME
AGREEMENT ON NOTABLE CAPE FOR OUR FORECAST AREA IS OVER RIVERSIDE
COUNTY AND PORTIONS OF LA PAZ. WILL CONTINUE TO EVALUATE THE NEED
FOR A FLASH FLOOD WATCH IN THOSE AREAS WITH JOSHUA TREE NATIONAL PARK
BEING MOST LIKLEY CANDIDATE. ELSEWHERE...WILL PLAN ON MAKING SOME
TWEAKS TO THE POPS TODAY TO DELAY ONSET FOR PHOENIX AREA AND TRIM
BACK OVER SOUTHERN GILA COUNTY.
&&
.PREVIOUS DISCUSSION ISSUED 341 AM MST/PDT...
PER 10Z IR SATELLITE IMAGERY AN MCV CONTINUES TO TRACK NORTHWARD
INTO SOUTHERN NEW MEXICO WITH DEBRIS CLOUDS EXPANDING WESTWARD ACROSS
CENTRAL ARIZONA AND SOUTHERN NEVADA. WITH THE SHORTWAVE MOVING TO THE
NORTHEAST AROUND THE HIGH PRESSURE...SOUTHEASTERLY FLOW CONTINUES TO
BRING MOISTURE /MIXING RATIOS 12-15 G/KG/ INTO SOUTHERN AND CENTRAL
ARIZONA. DEWPOINT READINGS THIS MORNING CONTINUE TO BE ELEVATED INTO
THE MID 60S. TEMPERATURES ARE RUNNING ABOUT 1-3 DEGREES COOLER THAN
THIS TIME YESTERDAY...LIKELY DUE TO LESS CLOUD COVER. THAT BEING
SAID...EXPECTING TO HAVE A BIT LONGER PERIOD OF CLEARING SKIES AND
MORE DAYTIME HEATING TODAY...AND THUS RAISED TEMPERATURES TODAY.
TODAY`S STORM CHANCES LOOK TO BE MORE DIURNALLY DRIVEN...FOCUSING ON
THE AFTERNOON AND EARLY EVENING HOURS FOR MOST OF CENTRAL AND
SOUTHWEST ARIZONA. DIFFLUENT MID TO UPPER LEVEL FLOW ASSOCIATED WITH
THE INVERTED TROUGH CIRCULATING AROUND THE HIGH WILL FOCUS THE
INSTABILITY ACROSS SOUTHEAST CALIFORNIA THIS MORNING INTO EARLY
AFTERNOON...WHERE THE BRUNT OF THE MOISTURE IS BEING HOUSED. NOTHING
OUTSTANDING WITH PWAT VALUES /1.7 - 1.8 INCH OUT OF YUMA/ NEARING
THE 90TH PERCENTILE FOR THE LOWER COLORADO RIVER VALLEY AND
SOUTHEAST CALIFORNIA. WITH DAYTIME HEATING AND INCREASED
MOISTURE...THE LACKING INGREDIENT WILL BE STRONG LIFT. MARGINAL
INSTABILITY WITH A WEAK STEERING FLOW AND DYNAMIC FEATURE DOES NOT
LOOK TOO PROMISING FOR AN OVERLY ACTIVE DAY ACROSS SOUTHEAST
CALIFORNIA...THOUGH NOT RULING OUT ALL ACTIVITY...AND THUS HAVE
DECIDED NOT TO ISSUE ANY HYDRO PRODUCT AT THIS TIME. FRIDAY`S
OUTLOOK IS MUCH OF THE SAME AS TODAY...THOUGHT WITH SLIGHTLY LESS
MOISTURE IN THE LOWER LEVELS...SO EXPECTING MOST OF THE CONVECTIVE
ACTIVITY TO REMAIN ACROSS EASTERN AND EAST CENTRAL ARIZONA.
WHILE A RIDGE OF HIGH PRESSURE REMAINS EVIDENT AND IN FAIR LOCATION
THROUGH THE WEEK AHEAD...THE WIND FLOW PATTERN SHIFTS SLIGHTLY TO A
SOUTHWESTERLY DIRECTION AND LOSES SOME OF THE PROPER MOISTURE. IN
COMPARISON TO CURRENT MIXING RATIOS OF 10-12 G/KG...BY MONDAY THE
VALUES ARE FORECAST TO DROP BELOW 8 G/KG AND A MORE CONFLUENT
LAMINAR FLOW SETTLES IN. NOTHING IN THE PATTERN AHEAD SHOWS A GREAT
DEAL OF PROMISING CONVECTIVE ACTIVITY AND LOOKS TO BE MORE OF A
PERSISTENT MILD MONSOON PATTERN...WITH MINIMALLY FLUCTUATING
TEMPERATURES AND STORM CHANCES EACH DAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SCT-BKN DEBRIS CLOUDS TO LINGER INTO A PORTION OF THE AM HOURS...
WHILE GRADUALLY THINNING AND CLEARING TOWARDS THE AFTN. EASTERLY SFC
WINDS WILL TRANSITION TO WESTERLY HEADINGS FOR THE AFTN...WITH A
WINDOW OF LIGHTER VRB HEADINGS AROUND MIDDAY. THUNDERSTORMS EXPECTED
TO DEVELOP AGAIN OVER PORTIONS OF THE HIGHER TERRAIN NORTH...EAST...
AND SOUTHEAST OF THE PHX AREA. CHANCES LOOK GOOD FOR OUTFLOW
INTRUSIONS INTO THE METRO POST 31/00Z...PSBLY FROM THE NORTH OR
SOUTHEAST. CANNOT RULE OUT A VCSH POP-UP ALONG THOSE
BOUNDARIES...SO INCLUDED VCSH MENTION FOR KIWA AND KSDL 31/03-04Z
TIME FRAME.
SOUTHEAST CALIFORNIA/SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH...
CLEARING SKIES SO FAR THIS MORNING AND MOSTLY CLEAR SKIES UPSTREAM
SHOULD ALLOW FOR AMPLE DAYTIME HEATING AND PTNL FOR AT LEAST
ISOLATED THUNDERSTORMS ACROSS SOUTHEAST CA...PARTICULARLY NEAR KBLH.
INCLUDED AFTN VCTS COVERAGE FOR KBLH. SFC WINDS TO MAINTAIN SOME
SOUTHERLY ORIENTATION DURING MUCH OF THE DAY WITH SPEEDS GNLY LESS
THAN 10 KTS...WITH PTNL FOR GUSTY WINDS AND DRASTIC WIND SHIFTS FROM
NEARBY THUNDERSTORMS AND LONG-TRAVELING OUTFLOWS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SATURDAY THROUGH WEDNESDAY...
MONSOONAL MOISTURE WILL SLOWLY BEGIN TO THIN ACROSS THE AREA...FIRST
ACROSS THE WESTERN FIRE DISTRICTS AND EVENTUALLY INTO THE ENTIRE
LOWER DESERT ELEVATIONS AND REGION BY EARLY NEXT WEEK. THIS WILL
RELEGATE STORM CHANCES BACK TOWARDS THE HIGHER TERRAIN AND FURTHER
TO THE EAST ACROSS AZ. THE SLIGHTLY DRIER AIRMASS AND BUILDING UPPER
RIDGE HEIGHTS WILL LEND THEMSELVES TOWARD WARMER SFC CONDITIONS...AT
OR ABOVE SEASONAL NORMALS. WINDS WILL FOLLOW FAMILIAR WARM SEASON
PATTERNS.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...DEWEY
AVIATION...NOLTE
FIRE WEATHER...NOLTE
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
946 AM PDT THU JUL 30 2015
.SYNOPSIS...
WARM AND HUMID TODAY WITH ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS OVER THE AREA. FLASH FLOOD WATCH FOR
MOUNTAINS/DESERTS/INLAND EMPIRE THROUGH THIS EVENING. DRIER...WITH
NEAR NORMAL HIGH TEMPERATURES...THIS WEEKEND INTO EARLY NEXT WEEK
AS HIGH PRESSURE BUILDS ALOFT. NIGHT/MORNING LOW CLOUDS ALONG THE
COAST AND BREEZY WESTERLY WIND THROUGH MOUNTAIN PASSES AND ALONG
DESERT MOUNTAIN SLOPES THROUGH THE PERIOD.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
AT 9 AM PDT...WATER VAPOR SATELLITE IMAGERY DISPLAYED A BROAD
UPPER-LEVEL RIDGE STRETCHING FROM THE LOWER MISSISSIPPI VALLEY TO
CENTRAL NEVADA...AND A WEAK UPPER-LEVEL LOW AROUND 200 MILES SSW
OF SAN DIEGO. THE 30/1200 UTC KNKX SOUNDING DISPLAYED A VERY MOIST
AND UNSTABLE PROFILE...WITH A CALCULATED PRECIPITABLE WATER OF
2.02 INCHES AND MOST-UNSTABLE CAPE OF 2030 J/KG. A WEAK UPPER-
LEVEL WAVE MOVING ACROSS THE REGION WAS GENERATING LIGHT SHOWERS
OVER PORTIONS OF THE SAN BERNARDINO COUNTY MOUNTAINS AND DESERTS.
WITH DIURNAL HEATING...CONDITIONS SHOULD COME TOGETHER LATE THIS
MORNING THROUGH THIS EVENING TO GENERATE SHOWERS AND THUNDERSTORMS
OVER THE REGION...MAINLY OVER THE DESERTS...MOUNTAINS AND THE
INLAND EMPIRE. THE 30/1500 UTC HRRR SHOWS SHOWER AND THUNDERSTORM
ACTIVITY DEVELOPING OVER THE SAN DIEGO AND RIVERSIDE COUNTY
MOUNTAINS AROUND NOON...THEN DEVELOPING OVER PORTIONS OF SW SAN
BERNARDINO COUNTY LATER THIS AFTERNOON AS CLOUDS CLEAR THE AREA.
THIS WILL LIKELY BE THE CASE GIVEN MODERATE NEGATIVE VORTICITY
ADVECTION IN THE WAKE OF THE UPPER-LEVEL WAVE MOVING OUT OF THE
AREA THIS MORNING. IF ANY OF THESE STORMS BECOME STATIONARY...OR
TRAIN OVER A LOCATION...THERE IS A GOOD POTENTIAL FOR FLASH
FLOODING. HOWEVER...MOST STORMS ARE EXPECTED TO MOVE AROUND 15 MPH
GIVEN THE MID AND UPPER-LEVEL WINDS. THE FLASH FLOOD WATCH FOR THE
MOUNTAINS...DESERTS AND INLAND EMPIRE REMAINS IN EFFECT THROUGH 8
PM PDT THIS EVENING. A WEAK UPPER-LEVEL WAVE MOVING ACROSS THE
REGION TONIGHT WILL CREATE THE POSSIBILITY OF AN ISOLATED
SHOWER/THUNDERSTORM OVER THE MOUNTAINS AND DESERTS.
ON FRIDAY...FLOW WILL SHIFT FROM SE TO MORE SOUTHERLY...ADVECTING
DRIER AIR INTO THE REGION. THIS WILL CREATE LESS OF A FLASH FLOOD
THREAT AND LOWER THE COVERAGE OF AFTERNOON THUNDERSTORMS COMPARED
TO TODAY. MODELS ARE TRENDING DRIER FOR THE WEEKEND INTO EARLY
NEXT WEEK AS THE AFOREMENTIONED UPPER-LEVEL RIDGE BUILDS TO THE
SE. WILL WAIT FOR THE 12 UTC MODEL RUNS BEFORE CHANGING THE POP
FORECAST. HOWEVER...CONFIDENCE IS INCREASING FOR DRY WEATHER FOR
THE WEEKEND THROUGH NEXT TUESDAY. THE 30/0600 GFS BRINGS MOISTURE
BACK INTO THE AREA NEXT WEDNESDAY...AND GENERATES THUNDERSTORMS
OVER THE MOUNTAINS AND DESERTS NEXT WEDNESDAY AND THURSDAY.
BUILDING HEIGHTS OVER THE AREA WILL HELP RAISE HIGH TEMPERATURES
TO NEAR NORMAL...AND MAINTAIN A SHALLOW MARINE LAYER WITH PATCHY
NIGHT/MORNING LOW CLOUDS/FOG ALONG THE COAST AND COASTAL VALLEYS.
NORMAL ONSHORE PRESSURE GRADIENTS WILL CREATE BREEZY WESTERLY
WINDS THROUGH MOUNTAIN PASSES AND ALONG DESERT MOUNTAIN SLOPES IN
THE AFTERNOONS/EVENINGS THROUGH THE PERIOD.
&&
.AVIATION...
301530Z...COAST/VALLEYS...SCT-BKN LOW CLOUDS PERSIST
OVER THE COASTAL BASIN AND INLAND IN/NEAR KCRQ WITH BASES NEAR 1500
FT MSL AND TOPS 2000 FT MSL. THE LOW CLOUDS WILL ERODE THE COAST
BETWEEN 30/1500-1800Z. THERE IS A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS THROUGH THIS EVENING ACROSS THE ENTIRE REGION...THOUGH
THE MOUNTAINS WILL BE FAVORED. HOWEVER...CONFIDENCE ON TIMING IS LOW
SO WILL MONITOR FOR VCTS INCLUSION IN THE TAFS. STRATUS WITH SIMILAR
BASES AND HEIGHTS AS THIS MORNING WILL PUSH BACK INLAND AFTER
31/0300Z.
MTNS/DESERTS...A CHANCE OF SHOWERS AND THUNDERSTORMS EXISTS THROUGH
THIS EVENING ACROSS THE MTS AND DESERTS. GREATEST STORM COVERAGE
WILL BE AFT 30/2000Z. THUNDERSTORM BASES WILL GENERALLY BE AOA 8000
FT MSL WITH TOPS TO 40000 FT MSL. THE MAIN THREATS FROM THESE STORMS
WILL BE BRIEF HEAVY RAIN...LOWERED VIS...AND FREQUENT CLOUD-TO-CLOUD
AND CLOUD-TO-GROUND LIGHTNING.
&&
.MARINE...
830 AM...THERE IS A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS OVER
THE INNER COASTAL WATERS THROUGH THIS EVENING AS AN UPPER LEVEL
DISTURBANCE MOVES OVER THE AREA. OTHERWISE...NO HAZARDOUS MARINE
WEATHER IS EXPECTED THROUGH SUNDAY.
&&
.BEACHES...
830 AM...THE ELEVATED SURF WILL SUBSIDE TODAY AS THE
SWELL DECLINES TO AROUND 2 FT AT 14-15 SEC...BUT THE RISK OF STRONG
RIP CURRENTS AND LIGHTNING CONTINUES THROUGH THE EVENING. THEREFORE
THE BEACH HAZARDS STATEMENT WILL CONTINUE THROUGH THIS EVENING. THE
SLOW DOWNWARD TREND IN THE SWELL WILL CONTINUE THROUGH THE
WEEKEND.
&&
.SKYWARN...
SKYWARN ACTIVATION MAY BE REQUESTED LATER TODAY.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...FLASH FLOOD WATCH UNTIL 8 PM PDT THIS EVENING FOR APPLE AND
LUCERNE VALLEYS-COACHELLA VALLEY-RIVERSIDE COUNTY MOUNTAINS-
SAN BERNARDINO COUNTY MOUNTAINS-SAN BERNARDINO AND
RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-SAN DIEGO COUNTY
DESERTS-SAN DIEGO COUNTY MOUNTAINS-SAN GORGONIO PASS NEAR
BANNING.
BEACH HAZARDS STATEMENT UNTIL 8 PM PDT THIS EVENING FOR ORANGE
COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.
PZ...NONE.
&&
$$
PUBLIC...JJT
AVIATION/MARINE/BEACHES...TS
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
949 PM PDT WED JUL 29 2015
.SYNOPSIS...
MONSOONAL MOISTURE AROUND STRONG HIGH PRESSURE OVER THE FOUR CORNERS
REGION WILL BRING WARM...HUMID WEATHER INTO THE REGION THROUGH
THURSDAY. SCATTERED SHOWERS AND THUNDERSTORMS ARE LIKELY OVER THE
MOUNTAINS AND DESERTS. SOME STORMS MAY DRIFT INTO THE INLAND VALLEYS
TONIGHT AND THURSDAY...AND POSSIBLY TO THE COAST AT TIMES. THE
AIRMASS DRIES OUT OVER THE WEEKEND INTO EARLY NEXT WEEK FOR LOWER
CHANCES FOR AFTERNOON THUNDERSTORMS OVER THE MOUNTAINS AND DESERTS.
THE MARINE LAYER WILL REMAIN MAINLY OVER THE COAST AND PORTIONS OF
THE VALLEYS.
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
RADAR THIS EVENING SHOWS THAT THUNDERSTORM ACTIVITY HAS DIMINISHED
SUBSTANTIALLY OVER THE FORECAST AREA. HOWEVER...NOCTURNAL
THUNDERSTORM AND SHOWER ACTIVITY LOOKS POSSIBLE LATE TONIGHT THROUGH
THURSDAY MORNING AS AN EASTERLY WAVE MOVES OVER THE REGION. WITH THE
WAVE WILL ALSO BE A SECOND AND MORE SIGNIFICANT SURGE OF MOISTURE
INTO THE AREA...WITH NAM12 SHOWING PRECIPITABLE WATER INCREASING TO
2 INCHES. THE NAM12 AND GFS40 SHOW THIS WAVE WELL...AND THE GFS40
CONTINUES TO PAINT A LARGE AREA OF LIGHT PRECIPITATION OVER SOUTHERN
CALIFORNIA IN ASSOCIATION WITH THE WAVE. THE HRRR HAS BEEN FLIP-
FLOPPING WITH EACH RUN WITH HOW MUCH ACTIVITY OCCURS WITH THIS
WAVE...WITH SOME RUNS SHOWING SOME LIGHT SHOWERS MOVING THROUGH THE
REGION...AND OTHER RUNS SHOWING SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS ALL THE WAY TO THE COAST. HOWEVER...THERE IS A GOOD
AMOUNT OF ELEVATED INSTABILITY FROM THE COAST THROUGH THE DESERTS
INDICATED BY THE WRF AND GFS BUFKIT FORECAST SOUNDINGS FOR TONIGHT
INTO TOMORROW...SO IF THE VORT MAX ASSOCIATED WITH THE WAVE IS ABLE
TO TRIGGER ACTIVITY...IT SHOULD RESULT IN A FAIR AMOUNT OF LIGHTNING
AS WELL. THE STORMS SHOULD BE MOVING SOMEWHAT QUICKLY...AS THE 700-
500 MB FLOW IS FORECAST TO BE 15-30 KT OUT OF THE EAST.
THE WAVE LOOKS TO MOVE OFF TO THE WEST BY LATE THURSDAY
MORNING...AND THE CLEARER SKIES BEHIND IT SHOULD RESULT IN GOOD DAY-
TIME HEATING AND INSTABILITY FOR MOUNTAIN AND DESERT THUNDERSTORMS
TO DEVELOP. THE INLAND EMPIRE SHOULD HAVE A GOOD CHANCE OF SEEING
STORMS AS WELL...AS THE WRF SHOWS THE ELSINORE CONVERGENCE BOUNDARY
SETTING UP BY MID-AFTERNOON. THE 700-500 MB FLOW WILL BE A LITTLE
LIGHTER...BUT STILL 15-20 KT OUT OF THE SOUTHEAST...SO STORMS MAY
STILL MOVE AT A DECENT PACE. HOWEVER...WITH HOW HIGH THE MOISTURE
AND INSTABILITY WILL BE...EVEN BRIEF HEAVY RAINFALL MAY BE ENOUGH TO
PRODUCE FLASH FLOODING...ESPECIALLY OVER RECENT BURN SCARS. A FLASH
FLOOD WATCH GOES INTO EFFECT EARLY THURSDAY MORNING AND CONTINUES
THROUGH EARLY THURSDAY EVENING FOR THE MOUNTAINS...DESERTS AND
INLAND EMPIRE. SOME STORMS COULD MAKE IT ALL THE WAY TO THE COAST AS
WELL...ALTHOUGH THE BETTER CHANCES FOR THAT WILL BE WITH THE
AFOREMENTIONED EASTERLY WAVE MOVING THROUGH LATE TONIGHT INTO
THURSDAY MORNING.
THE REST OF THE FORECAST REMAINS ON TRACK.
THE LAST PART OF THE PREVIOUS DISCUSSION ISSUED AT 145 PM FOLLOWS...
ON THURSDAY NIGHT AND FRIDAY THE UPPER LEVEL WINDS SHIFT FROM THE
SOUTHEAST TO THE SOUTH AND MOST OF THE THUNDERSTORM ACTIVITY WILL BE
CONFINED TO THE MOUNTAINS AND DESERTS. OVER THE WEEKEND THE AIRMASS
DRIES OUT WITH PRECIPITABLE WATER LOWERING TO LESS THAN 1.00". THIS
WILL LOWER THE THUNDERSTORM THREAT OVER THE MOUNTAINS AND DESERTS
SATURDAY AND SUNDAY.
THE LONG RANGE PROGS KEEP THE SUBTROPICAL HIGH OVER THE SOUTHWEST
AND BRING IN A SMALL SURGE OF MONSOON MOISTURE BACK INTO SOUTHERN
CALIFORNIA FOR CONTINUED CHANCES OF AFTERNOON THUNDERSTORMS OVER THE
MTNS. LATE NEXT WEEK THE UPPER HIGH WILL BE SUPPRESSED SOUTHWARD BY
A TROUGH DEEPENING ALONG THE NORTHERN CALIFORNIA COAST. DRIER
SOUTHWEST FLOW WILL CURTAIL THUNDERSTORM DEVELOPMENT AS THE DEEPEST
MONSOON MOISTURE WILL BE FORCED SOUTH AND EAST OF OUR AREA.
MARINE LAYER CLOUDS CLUNG TO THE BEACHES THIS AFTERNOON AND A
SIMILAR OCCURRENCE IS POSSIBLE THURSDAY. A STRONG INVERSION WILL
REMAIN IN PLACE THROUGH FRIDAY WHICH MAY KEEP LOW CLOUDS AT THE
BEACHES INTO THE AFTERNOON.
&&
.AVIATION...
300315Z...COAST/VALLEYS...SCT CLOUDS ACROSS THE AREA FROM REMNANT
THUNDERSTORMS IN THE MOUNTAINS AND SOME REMNANT MARINE STRATUS ALONG
THE COAST WILL CONTINUE OVERNIGHT. THE BIGGER QUESTION IS WILL
NOCTURNAL THUNDERSTORMS OCCUR WITH THE WEAK UPPER LEVEL DISTURBANCE
OVER SOUTHEAST CA AND W AZ MOVING OVERHEAD? MODELS ARE LOOKING GOOD
FOR SOME DEVELOPMENT...BUT ONE RIGHT OVER A TERMINAL SITE IS THE
DIFFICULT QUESTION. IT IS LIKELY FLIGHT PATTERNS WILL NOTE SOME
CONVECTION SO VICINITY THUNDER IS IN THE FORECAST WITH GREATEST
CHANCES AFTER 300700Z TO AROUND 310200Z. MOST OF THIS WILL BE HIGH
BASES AT OR ABOVE 8000 FT MSL AND MOST OF THE AFTERNOON THUNDERSTORM
RISK...301900-310200Z... WILL BE MORE IN THE MOUNTAINS AND DESERT
WITH JUST REMNANT CLOUD ELEMENTS DRIFTING OVER THE AIRPORTS.
MTNS/DESERTS...THE SLIGHT CHANCE FOR SHOWERS AND THUNDERSTORMS WILL
CONTINUE THROUGH THE NIGHT UNTIL AROUND 301500Z. A BRIEF BREAK MAY
OCCUR BEFORE THINGS START REGENERATING WITH THE HEAT OF THE DAY FROM
301900-310200Z. THERE IS A RISK OF CB WITH TOPS TO 40000 FT MSL
OVERNIGHT AND AGAIN IN THE AFTERNOON AND EVENING ON THURSDAY. BASES
WILL GENERALLY BE AT OR ABOVE 8000 FT MSL EXCEPT LOWERING NEAR
THUNDERSTORMS.
&&
.MARINE...
8 PM...THERE IS A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS OVER
THE NEARBY COASTAL WATERS AND ESTUARIES OVERNIGHT THROUGH THURSDAY
AFTERNOON AS AN UPPER LEVEL DISTURBANCE MOVES OVER THE AREA.
OTHERWISE...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH SUNDAY.
&&
.BEACHES...
8 PM...ELEVATED SURF ON WEDNESDAY CAUSED A FEW PROBLEMS INCLUDING
STRONG RIP CURRENTS AT THE BEACHES OF SAN DIEGO COUNTY AND SOUTHERN
ORANGE COUNTY. THE SURF IS SUBSIDING THURSDAY...BUT THE RISK OF
LIGHTNING INCREASES OVERNIGHT THROUGH THURSDAY. LARGE RIP CURRENTS
ARE POSSIBLE AND LIGHTNING...THEREFORE THE BEACH HAZARD STATEMENT
WILL CONTINUE THROUGH THURSDAY EVENING. SURF CONDITIONS WILL IMPROVE
SLIGHTLY DURING THE DAY THURSDAY AS THE WELL DECLINES TO AROUND 2 FT
AT 14-15 SEC...BUT THE RIP CURRENT RISK WILL REMAIN HIGH. THE SLOW
DOWNWARD TREND IN THE SWELL WILL CONTINUE FOR FRIDAY THROUGH THE
WEEKEND. AGAIN...THE THUNDERSTORM POTENTIAL AND DANGEROUS CLOUD TO
BEACH/WATER LIGHTNING IS THERE OVERNIGHT TONIGHT INTO THURSDAY
EVENING.
&&
.SKYWARN...
SKYWARN ACTIVATION MAY BE REQUESTED ON THURSDAY.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...FLASH FLOOD WATCH FROM 3 AM PDT THURSDAY THROUGH THURSDAY
EVENING FOR APPLE AND LUCERNE VALLEYS-COACHELLA VALLEY-
RIVERSIDE COUNTY MOUNTAINS-SAN BERNARDINO COUNTY MOUNTAINS-
SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE INLAND
EMPIRE-SAN DIEGO COUNTY DESERTS-SAN DIEGO COUNTY MOUNTAINS-
SAN GORGONIO PASS NEAR BANNING.
BEACH HAZARDS STATEMENT THROUGH THURSDAY EVENING FOR ORANGE
COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS.
PZ...NONE.
&&
$$
PUBLIC...HARRISON
AVIATION/MARINE/BEACHES...PIERCE
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1012 AM MDT THU JUL 30 2015
.UPDATE...
ISSUED AT 1012 AM MDT THU JUL 30 2015
NO CHANGES TO THE FORECAST NEEDED AT THIS TIME. MODELS ARE RATHER
TENTATIVE IN GENERATING MUCH QPF ACROSS NORTHEAST COLORADO THIS
AFTERNOON AND EVENING. THE AXIS OF THE UPPER RIDGE APPEARS TO
STILL BE SOUTH OF US WITH THE DEEPER MONSOONAL MOISTURE BEING HELD
SOUTH OF THAT FEATURE. FLOW ALOFT OVER OUR FORECAST AREA IS WEAK
AND NORTHWESTERLY...REMAINING DRIER AND MORE STABLE. SINCE SOME OF
THE MOISTURE HAS MADE IT INTO SOUTHERN COLORADO...WILL HOLD ON TO
THE LOW CHANCES OF AFTERNOON SHOWERS OVER PARK COUNTY AND THE
PALMER DIVIDE.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 345 AM MDT THU JUL 30 2015
BROAD HIGH PRESSURE ALOFT CONTINUES ACROSS THE SOUTHERN TIER
STATES...WITH SOME BUILDING OF THE HIGH FURTHER WEST AND NORTH ACROSS
THE GREAT BASIN. THIS WILL KEEP SOME DRIER...WESTERLY FLOW ACROSS
NORTHERN COLORADO...WHILE SOUTHERN COLORADO REMAINS UNDER A
WETTER...SOUTHWEST FLOW. HIGHER POPS TODAY AGAIN WILL REMAIN OVER
SOUTHERN PORTIONS OF CWA...ESPECIALLY OVER PARK COUNTY AND
EXTENDING FURTHER EAST ACROSS THE PALMER DIVIDE. SURFACE TROF OVER
EASTERN COLORADO BECOMES ELONGATED ACROSS NORTHEAST COLORADO WHICH
RESULTS IN SOME WEAK CONVERGENCE FROM THE PALMER DIVIDE AND
STRETCHES THROUGH FAR NE PLAINS. IN ADDITION...JET STREAK ACROSS
THE MIDWEST MAY PRODUCE SOME WEAK LIFT OVER THE PLAINS AS WELL.
INDEED...THE RAP DOES SOME HAVE SOME WEAK LIFT IN THE 700MB QG
VERTICAL VELOCITY FIELD.
TEMPERATURES TODAY WILL BE A FEW DEGREES HIGHER TODAY OVER
NORTHERN SECTIONS WITH THE DRIER AND SLIGHTLY WARMER AIRMASS. MAIN
CHANGE WAS TO EXTEND POPS A BIT FURTHER NORTH ON THE FAR PLAINS
THROUGH THIS EVENING.
SATELLITE IMAGERY THIS MORNING SHOWING SOME STRATUS AND POTENTIAL
FOG DEVELOPING OVER LINCOLN COUNTY AND WILL TO TO GRIDS TO COVER
THIS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 AM MDT THU JUL 30 2015
MODELS ARE STILL IN AGREEMENT AS THEY CONTINUE TO EXTEND THE
UPPER RIDGE NORTHWESTWARD ACROSS THE NORTHERN GREAT BASIN PLACING
NERN COLORADO UNDER A SOMEWHAT DRIER NWLY MID-LEVEL FLOW FRIDAY
MORNING. MEANWHILE SUBTROPICAL MOISTURE POOLING ACROSS NORTHERN
NEW MEXICO/NERN ARIZONA IS FORECAST TO FLOW NORTHWARD INTO SRN
COLORADO EARLY IN THE DAY AND UP ALONG THE NORTHERN FRONT RANGE
DURING THE AFTERNOON. DAYTIME HEATING COUPLED WITH THE INCREASE
IN PRECIPITABLE WATER SHOULD MANAGE TO PRODUCE SCATTERED T-STORMS
OVER THE FRONT RANGE MTNS DURING THE AFTERNOON AND POSSIBLY AS
EARLY AS LATE MORNING OVER THE MOSQUITO RANGE AND SOUTH PARK IN
PARK COUNTY. NWLY TRANSPORT WINDS SHOULD THEN MOVE THESE STORMS
OVER THE ADJACENT HIGH PLAINS DURING THE MID AND LATE AFTERNOON
HRS WHERE THEY SHOULD LINGER THRU MID-EVENING PRODUCING GUSTY
WINDS AND BRIEF LIGHT TO MODERATE RAINFALL. PRECIP CHANCES IN THE
30-40 PCT RANGE IN THE HIGH COUNTRY AND 10-20 PCT AT LOWER
ELEVATIONS. THE PRESENCE OF A STRONG MID-LEVEL CAP SHOULD HINDER
THE FORMATION OF DEEP UPDRAFTS AND THEREFORE STORMS SHOULD STAY
WELL BELOW SEVERE CRITERIA. HIGHS ON FRIDAY STILL BELOW AVERAGE
WITH MID/UPPER 80S WITH MAINLY 70S IN THE HIGH COUNTRY.
LOOKING AHEAD TO THE WEEKEND...THE NEGATIVELY TILTED UPPER RIDGE
OVER THE WESTERN CONUS CONTINUES TO BUILD NORTHWARD ON SATURDAY
WHICH PUSHES THE SUBTROPICAL MOISTURE PLUME SOUTHWARD RESULTING IN
DRIER AND WARMER CONDITIONS FOR THE CWA. THEREFORE SHOULD SEE LESS
STORM ACTIVITY ON SATURDAY...WITH THE BEST CHANCE FOR STORMS OVER
THE HIGHER TERRAIN SOUTH OF INTERSTATE 70. ON SUNDAY...THE UPPER
RIDGE SHIFTS EAST WITH LIGHT W-NWLY FLOW MOVING OVER THE FCST AREA.
SUBTROPICAL MOISTURE TRAPPED BENEATH THE RIDGE REVERSES ITS COURSE
AND BEGINS FLOWING NORTHWARD ACRS COLORADO. SHOULD SEE A FEW MORE T-
STORMS IN THE HIGH COUNTRY WITH ONLY A SLIGHT CHANCE ON THE NEARBY
PLAINS. HIGHS ON SUNDAY CREEP UP TO NEAR ABOVE AVERAGE.
MONDAY THROUGH WEDNESDAY...THE UPPER RIDGE IS STILL PROGGED TO
REMAIN OVER THE ROCKY MTN REGION WITH LITTLE DAY-TO-DAY CHANGE IN
WEATHER. ALTHOUGH THE ECMWF SHOWS A RATHER VIGOROUS SHORTWAVE
ROTATING ACROSS THE STATE ON MONDAY. THIS IS NEW IN THE MODEL. SO
WILL NOT BASE TOO MUCH OF THE FCST ON THIS FEATURE AT THE PRESENT
TIME. EXPECT TEMPERATURES TO RANGE FROM NEAR TO SLIGHTLY ABOVE
AVERAGE DURING THE PERIOD...WITH A CHANCE OF AFTERNOON AND EVENING T-
STORMS MAINLY IN AND NEAR THE MTNS EACH DAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z FRIDAY MORNING)
ISSUED AT 1012 AM MDT THU JUL 30 2015
MINIMAL AVIATION IMPACTS EXPECTED THROUGH THIS AFTERNOON. SHOWERS
AND THUNDERSTORMS ARE EXPECTED TO BE SOUTH OF THE DENVER
AREA...POSSIBLY OVER THE PALMER DIVIDE. SURFACE PRESSURE GRADIENTS
HAVE RELAXED OVER THE PAST 24 HOURS...LEADING TO LESS
SOUTHEASTERLY WINDS TODAY. STILL EXPECT WINDS TO BECOME MORE
EASTERLY DURING THE AFTERNOON HOURS. CHANCES OF SHOWERS OVER THE
DENVER AIRPORTS ARE SO LOW THAT THEY ARE NOT GOING TO BE MENTIONED
IN THE TAFS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DANKERS
SHORT TERM...ENTREKIN
LONG TERM...BAKER
AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
346 AM MDT THU JUL 30 2015
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 345 AM MDT THU JUL 30 2015
BROAD HIGH PRESSURE ALOFT CONTINUES ACROSS THE SOUTHERN TIER
STATES...WITH SOME BUILDING OF THE HIGH FURTHER WEST AND NORTH ACROSS
THE GREAT BASIN. THIS WILL KEEP SOME DRIER...WESTERLY FLOW ACROSS
NORTHERN COLORADO...WHILE SOUTHERN COLORADO REMAINS UNDER A
WETTER...SOUTHWEST FLOW. HIGHER POPS TODAY AGAIN WILL REMAIN OVER
SOUTHERN PORTIONS OF CWA...ESPECIALLY OVER PARK COUNTY AND
EXTENDING FURTHER EAST ACROSS THE PALMER DIVIDE. SURFACE TROF OVER
EASTERN COLORADO BECOMES ELONGATED ACROSS NORTHEAST COLORADO WHICH
RESULTS IN SOME WEAK CONVERGENCE FROM THE PALMER DIVIDE AND
STRETCHES THROUGH FAR NE PLAINS. IN ADDITION...JET STREAK ACROSS
THE MIDWEST MAY PRODUCE SOME WEAK LIFT OVER THE PLAINS AS WELL.
INDEED...THE RAP DOES SOME HAVE SOME WEAK LIFT IN THE 700MB QG
VERTICAL VELOCITY FIELD.
TEMPERATURES TODAY WILL BE A FEW DEGREES HIGHER TODAY OVER
NORTHERN SECTIONS WITH THE DRIER AND SLIGHTLY WARMER AIRMASS. MAIN
CHANGE WAS TO EXTEND POPS A BIT FURTHER NORTH ON THE FAR PLAINS
THROUGH THIS EVENING.
SATELLITE IMAGERY THIS MORNING SHOWING SOME STRATUS AND POTENTIAL
FOG DEVELOPING OVER LINCOLN COUNTY AND WILL TO TO GRIDS TO COVER
THIS.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 345 AM MDT THU JUL 30 2015
MODELS ARE STILL IN AGREEMENT AS THEY CONTINUE TO EXTEND THE
UPPER RIDGE NORTHWESTWARD ACROSS THE NORTHERN GREAT BASIN PLACING
NERN COLORADO UNDER A SOMEWHAT DRIER NWLY MID-LEVEL FLOW FRIDAY
MORNING. MEANWHILE SUBTROPICAL MOISTURE POOLING ACROSS NORTHERN
NEW MEXICO/NERN ARIZONA IS FORECAST TO FLOW NORTHWARD INTO SRN
COLORADO EARLY IN THE DAY AND UP ALONG THE NORTHERN FRONT RANGE
DURING THE AFTERNOON. DAYTIME HEATING COUPLED WITH THE INCREASE
IN PRECIPITABLE WATER SHOULD MANAGE TO PRODUCE SCATTERED T-STORMS
OVER THE FRONT RANGE MTNS DURING THE AFTERNOON AND POSSIBLY AS
EARLY AS LATE MORNING OVER THE MOSQUITO RANGE AND SOUTH PARK IN
PARK COUNTY. NWLY TRANSPORT WINDS SHOULD THEN MOVE THESE STORMS
OVER THE ADJACENT HIGH PLAINS DURING THE MID AND LATE AFTERNOON
HRS WHERE THEY SHOULD LINGER THRU MID-EVENING PRODUCING GUSTY
WINDS AND BRIEF LIGHT TO MODERATE RAINFALL. PRECIP CHANCES IN THE
30-40 PCT RANGE IN THE HIGH COUNTRY AND 10-20 PCT AT LOWER
ELEVATIONS. THE PRESENCE OF A STRONG MID-LEVEL CAP SHOULD HINDER
THE FORMATION OF DEEP UPDRAFTS AND THEREFORE STORMS SHOULD STAY
WELL BELOW SEVERE CRITERIA. HIGHS ON FRIDAY STILL BELOW AVERAGE
WITH MID/UPPER 80S WITH MAINLY 70S IN THE HIGH COUNTRY.
LOOKING AHEAD TO THE WEEKEND...THE NEGATIVELY TILTED UPPER RIDGE
OVER THE WESTERN CONUS CONTINUES TO BUILD NORTHWARD ON SATURDAY
WHICH PUSHES THE SUBTROPICAL MOISTURE PLUME SOUTHWARD RESULTING IN
DRIER AND WARMER CONDITIONS FOR THE CWA. THEREFORE SHOULD SEE LESS
STORM ACTIVITY ON SATURDAY...WITH THE BEST CHANCE FOR STORMS OVER
THE HIGHER TERRAIN SOUTH OF INTERSTATE 70. ON SUNDAY...THE UPPER
RIDGE SHIFTS EAST WITH LIGHT W-NWLY FLOW MOVING OVER THE FCST AREA.
SUBTROPICAL MOISTURE TRAPPED BENEATH THE RIDGE REVERSES ITS COURSE
AND BEGINS FLOWING NORTHWARD ACRS COLORADO. SHOULD SEE A FEW MORE T-
STORMS IN THE HIGH COUNTRY WITH ONLY A SLIGHT CHANCE ON THE NEARBY
PLAINS. HIGHS ON SUNDAY CREEP UP TO NEAR ABOVE AVERAGE.
MONDAY THROUGH WEDNESDAY...THE UPPER RIDGE IS STILL PROGGED TO
REMAIN OVER THE ROCKY MTN REGION WITH LITTLE DAY-TO-DAY CHANGE IN
WEATHER. ALTHOUGH THE ECMWF SHOWS A RATHER VIGOROUS SHORTWAVE
ROTATING ACROSS THE STATE ON MONDAY. THIS IS NEW IN THE MODEL. SO
WILL NOT BASE TOO MUCH OF THE FCST ON THIS FEATURE AT THE PRESENT
TIME. EXPECT TEMPERATURES TO RANGE FROM NEAR TO SLIGHTLY ABOVE
AVERAGE DURING THE PERIOD...WITH A CHANCE OF AFTERNOON AND EVENING T-
STORMS MAINLY IN AND NEAR THE MTNS EACH DAY.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 345 AM MDT THU JUL 30 2015
SURFACE WINDS BEGINNING TO TURN MORE SOUTHWEST AND WEST AT DEN/BJC
AS SURFACE LOW BEGINS TO PUSH EAST. WIND FIELDS EXPECTED MORE WEST
AND NORTHWEST THIS AM BEFORE TURNING LIGHT NORTHEAST THIS
AFTERNOON. MUCH OF THE STORMS TODAY WILL BE SOUTH OF TERMINALS BUT
WEAK CONVERGENCE MAY HELP SPARK AN ISOLATED STORM FROM APA TO BKF
VICINITY. CONVERGENCE AT THIS POINT LOOKS LOW ENOUGH STILL NOT TO
MENTION IN TERMINAL FORECASTS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ENTREKIN
LONG TERM...BAKER
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS ALBANY NY
1030 PM EDT FRI JUL 31 2015
.SYNOPSIS...
AN ISOLATED SHOWER OR THUNDERSTORM WILL BE POSSIBLE FOR THIS FIRST
WEEKEND OF AUGUST AS A SERIES OF UPPER LEVEL DISTURBANCES MOVES
ACROSS THE REGION. TEMPERATURES WILL BE SEASONABLE ALONG WITH
COMFORTABLE HUMIDITY LEVELS. A COLD FRONT IS EXPECTED TO IMPACT
THE REGION ON MONDAY WITH A BETTER CHANCE FOR SCATTERED SHOWERS
AND THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 1030 PM EDT...SHOWERS AND EVEN A FEW RUMBLES OF THUNDER CONTINUED
TO THE LEE OF LAKE ONTARIO...JUST MISSING NORTHERN HERKIMER COUNTY.
ANOTHER WEAKER SHOWER WAS WORKING INTO GREENE COUNTY.
FOR THE REMAINDER OF THE OVERNIGHT IT LOOKS AS IF THE BEST FORCING WILL STAY
ACROSS OUR NORTHERN AREA WHERE SHOWERS ARE POSSIBLE. BY DAYBREAK...THIS FORCING
(WEAK LOW LEVEL CONVERGENCE AND AREA UNDER THE RR REGION OF A
80KT UPPER LEVEL JET)...WILL SHIFT DOWN TOWARD THE CAPITAL REGION.
THE WIND HAS DECOUPLED IN MOST PLACES. AS A RESULT...TEMPERATURES HAVE DROPPED
QUITE BIT...MAINLY INTO THE 60S.
FOR THE OVERNIGHT...LOOK FOR A VARIABLY CLOUDY SKY NORTH OF THE CAPITAL REGION...
PARTLY CLOUDY FURTHER SOUTH. SHOWERS WILL BE WIDELY SCATTERED MAINLY WELL
NORTH I-90 AND AMOUNTS OF RAINFALL SHOULD BE LIGHT. LOWS WILL GENERALLY
BE WITHIN A FEW DEGREES OF 60.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
THIS FIRST HALF OF THE WEEKEND OF AUGUST WILL FEATURE GRADUAL
FALLING HEIGHTS ALONG WITH A WEAK SURFACE TROUGH TO ASSIST WITH
MAINLY DIURNAL SHOWERS/STORMS. H500 NEGATIVE TEENS CELSIUS ALONG
WITH AN INCREASE IN SHEAR MAGNITUDES AND STEEPER LAPSE RATES...MAINLY
ACROSS THE NORTHERN PORTIONS OF OUR REGION...FOR INITIALLY
CONVECTION DEVELOPING ACROSS THE TERRAIN THEN MIGRATING INTO THE
VALLEYS. PER THE PREVIOUS EXCELLENT DISCUSSION...INSTABILITY
REMAINS IN QUESTION WITH THE NAM REMAINING MORE ROBUST THAN THE
GFS/ECMWF. PER SPC...SWODY2 PLACES A MARGINAL RISK ACROSS NORTHERN
NEW ENGLAND WITH GENERAL THUNDER ACROSS THE REMAINDER OF THE
REGION. WITHIN THE DEEPER CONVECTIVE ELEMENTS...SOME HAIL WILL BE
POSSIBLE BUT NOT MENTION IN THE GRIDS/FORECAST AT THIS TIME.
MOST OF THIS CONVECTION WILL DIMINISH WITHIN A COUPLE OF HOURS OF
SUNSET. VARIABLE CLOUD COVERAGE ACROSS THE REGION AND WHERE
PRECIPITATION DOES OCCUR...PATCHY FOG WILL BE THE RESULT.
SEASONABLE OVERNIGHT LOWS ONCE AGAIN.
SUNDAY...THE GLOBAL MODELS SUGGEST HEIGHTS SLOWLY RISE IN ADVANCE
OF THE UPSTREAM UPPER TROUGH AND COLD FRONT APPROACH. AT THIS
TIME...THE NAM DOES SEEM OVERLY AGGRESSIVE WITH MORE ROBUST
CONVECTION THAN THE GLOBAL MODEL CONSENSUS. FOR NOW...WE WILL KEEP
THE WEATHER DRY FOR PORTIONS OF THE MID HUDSON VALLEY...BERKS AND
INTO LITCHFIELD COUNTY. CHC-SCT POPS FOR THE CAPITAL
REGION...MOHAWK VALLEY...CATSKILLS...SOUTHERN GREENS...LAKE
GEORGE SARATOGA REGION AND THE DACKS. AS THE H850 TEMPS REBOUND
BACK INTO THE POSITIVE TEENS...THIS TOO WILL HAVE AN IMPACT TO OUR
TEMPERATURES WITH TEMPERATURES GENERALLY IN THE 80-85F DEGREE
RANGE.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AT THE START OF THE LONG TERM PERIOD...A LARGE CLOSED OFF LOW AT 500
HPA WILL BE SITUATED OVER NORTHERN ONTARIO. AT THE LEADING EDGE OF
THIS FEATURE WILL BE A STRONG SFC COLD FRONT WHICH WILL BE MOVING
TOWARDS THE AREA ON MONDAY FROM THE GREAT LAKES. AHEAD OF THIS
SYSTEM...A WARM AND HUMID AIR MASS WILL BE IN PLACE...WITH TEMPS
WELL INTO THE 80S TO NEAR 90. AS THE FRONT MOVES THROUGH THE
REGION...A BAND OF SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE
FRONT. CONSIDERING THE STRONG DYNAMICS ASSOCIATED WITH THIS
SYSTEM...WE WILL HAVE TO MONITOR THE POTENTIAL FOR SOME STRONG TO
SEVERE STORMS...ALTHOUGH THIS MAY ULTIMATELY DEPEND ON THE TIMING OF
THE BOUNDARY AND AMOUNT OF INSTABILITY IN PLACE. SHOWERS AND
THUNDERSTORMS SHOULD END ON MONDAY EVENING WITH THE PASSAGE OF THE
COLD FRONT.
THE UPPER LEVEL SHORTWAVE TROUGH WILL SHIFT TOWARDS EASTERN CANADA
AND THE NORTHEASTERN US FOR TUESDAY THROUGH THURSDAY. WITH THE
LOWERING HEIGHTS OVERHEAD...TEMPS WILL BE A LITTLE COOLER THAN
RECENT DAYS AND IT WILL BE SOMEWHAT LESS HUMID AS WELL. TEMPS WILL
MAINLY BE IN THE 70S TO NEAR 80 FOR TUESDAY THROUGH THURSDAY. IN
ADDITION...THE COOL TEMPS ALOFT WILL HELP PROMOTE SOME DIURNALLY
FORCED SHOWERS FOR THE AFTN AND EARLY EVENING HOURS...BUT COVERAGE
WILL BE FAIRLY ISOLATED. OVERNIGHT LOWS WILL MAINLY BE IN THE 50S.
THE FLOW ALOFT WILL START TO BECOME MORE ZONAL FOR LATE IN THE WEEK
BY FRIDAY...AS THE TROUGH STARTS TO PULL INTO ATLANTIC CANADA. WILL
CONTINUE TO MAINTAIN SLIGHT CHC POPS IN CASE THE TROUGH HANGS IN
LONGER...AS SUGGESTED BY THE LATEST 12Z ECMWF...WITH TEMPS NEAR OR
SLIGHTLY BELOW NORMAL.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
WITH THE EXCEPTION OF KGFL...VFR CONDITIONS ARE LIKELY TO HOLD
THROUGH THE TAF PERIOD. A FEW SHOWERS MIGHT IMPACT KGFL THROUGH
02Z SO VCSH THERE UNTIL 02Z. AT KGFL...WE THINK SOME MIST WILL
FORM AROUND 08Z...MOSTLY LIKELY DOWN TO JUST MVFR...BUT THIS
ASSUMES A DECREASE IN CLOUDS OVERNIGHT AND NO WIND.
WENT WITH MIFG FROM 08Z-11Z AT KPSF AND KPOU TO REFLECT THE
OUTSIDE POSSIBILITY THAT MVFR FOG MIGHT FORM.
AT KALB...WITH A LITTLE MORE OF A SOUTH WIND EXPECTED...KEPT FOG
OUT OF THE TAF FOR NOW.
ANY FOG WILL DISSIPATE BY 12Z SAT...WHICH SHOULD LEAVE A MAINLY
VFR DAY. A WEAK COLD FRONT WILL CROSS THE TAF SITES...INCREASE
CLOUDS WITH BASES OVER 3000 FEET AND THE POSSIBILITY OF A FEW
SHOWERS. PLACED VCSH IN ALL BUT KPOU TAF. WE START THIS ABOUT 16Z
ALONG WITH A WIND SHIFT BY 18Z...TO THE WEST AROUND
10KTS...GUSTING TO 18KTS AT KALB.
THERE IS AN OUTSIDE CHANCE OF A THUNDERSTORM WITH THE PASSAGE OF
THE COLD FRONT BUT CONFIDENCE TOO LOW FOR ANYTHING OTHER THAN A
VCSH AT THIS TIME.
OUTLOOK...
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX.
SUNDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
MONDAY: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA...TSRA.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
TUESDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
WEDNESDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
&&
.FIRE WEATHER...
MINIMAL FIRE WEATHER CONCERNS THROUGH THE WEEKEND AS A COUPLE OF
DISTURBANCES WILL RESULT IN ISOLATED TO WIDELY SCATTERED SHOWERS
AND THUNDERSTORMS.
RELATIVE HUMIDITY VALUES ARE EXPECTED TO INCREASING TO MAXIMUM
VALUES OF 85 TO 100 PERCENT TONIGHT. MIN RH VALUES SATURDAY WILL
DROP TO AROUND 40 TO 50 PERCENT DURING THE AFTERNOON.
WINDS INTO THIS EARLY EVENING WILL BE WESTERLY AROUND 10 TO 15
MPH WITH OCCASIONAL GUSTS TO 20 TO 25 MPH...DECREASING TO AROUND
5 MPH TONIGHT. WINDS ON SATURDAY WILL BE SOUTHWEST AT 5 TO 15 MPH.
&&
.HYDROLOGY...
AN ISOLATED SHOWER IS POSSIBLE THIS EVENING...THEN ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS ARE FORECAST FROM SATURDAY
INTO EARLY NEXT WEEK...MAINLY DURING THE AFTERNOON AND EVENING
HOURS. WIDESPREAD HEAVY RAINFALL ISN/T EXPECTED...BUT ANY
THUNDERSTORM WILL BE CAPABLE OF PRODUCING LOCALLY HEAVY DOWNPOURS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...HWJIV/BGM
NEAR TERM...HWJIV/BGM
SHORT TERM...BGM/JPV
LONG TERM...FRUGIS
AVIATION...HWJIV
FIRE WEATHER...BGM/JPV
HYDROLOGY...FRUGIS/BGM/JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
423 PM EDT THU JUL 30 2015
.SYNOPSIS...
WITH A COLD FRONT MOVING ACROSS THE REGION...SOME SHOWERS
AND THUNDERSTORMS WILL CONTINUE INTO THE EARLY EVENING HOURS. BEHIND
THIS BOUNDARY...LESS HUMID AIR WILL MOVE INTO THE AREA FOR TONIGHT
INTO FRIDAY...ALTHOUGH TEMPERATURES WILL CONTINUE TO BE WARM ON
FRIDAY. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL RETURN ON
SATURDAY...WITH TEMPERATURES SLIGHTLY ABOVE NORMAL LEVELS.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 423 PM EDT...COLD FRONT IS IN THE PROCESS OF MOVING ACROSS
THE CWA. THE BOUNDARY IS ALREADY THROUGH THE WESTERN AND CENTRAL
PARTS OF THE REGION. WINDS HAVE SWITCHED TO THE W-NW BEHIND THE
BOUNDARY...INCLUDING THE CAPITAL REGION...AND DEWPOINTS ARE
SLOWING STARTING TO FALL.
MEANWHILE...ALONG AND AHEAD OF THE BOUNDARY...SOME SHOWERS AND
THUNDERSTORMS ARE STILL ONGOING. THE STEADIEST/HEAVIEST
THUNDERSTORM ACTIVITY IS SOUTH OF THE AREA OVER THE LOWER HUDSON
VALLEY...AND COASTAL AND CENTRAL CT. HOWEVER...SOME ACTIVITY
CONTINUES OVER DUTCHESS/LITCHFIELD COUNTIES...AND SOME ADDITIONAL
ISOLATED TO SCATTERED SHOWERS/THUNDERSTORMS ARE POSSIBLE ALONG THE
IMMEDIATE FRONTAL BOUNDARY OVER THE NEXT FEW HOURS...AS IT
CONTINUES TO SLOWLY SETTLE SOUTH AND EAST. THE 3KM HRRR SUGGEST
THIS WILL CONTINUE TO BE A POSSIBILITY FOR THESE FAR SOUTHEASTERN
AREAS TILL ABOUT 8 TO 10 PM...WHEN FINALLY THE FRONT WILL BE
THROUGH THE REGION.
BEHIND THE FRONT...DEWPOINTS WILL CONTINUE TO FALL OVERNIGHT WITH
DECREASING CLOUDS. SOME PATCHY FOG WILL BE POSSIBLE...ESP FOR
SOUTHERN AND EASTERN AREAS WHERE THE FRONT WILL MOVE THROUGH
LAST...AS WELL AS ACROSS AREAS THAT SAW SIGNIFICANT RAINFALL ON
THURSDAY AS WELL.
MIN TEMPS LOOK TO BE IN THE UPPER 50S TO MID 60S IN MANY
AREAS...ALTHOUGH TEMPS WILL BE SLIGHTLY COOLER OVER THE
ADIRONDACKS AND SRN GREENS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
QUIET WEATHER IS EXPECTED FOR FRIDAY AS HIGH PRESSURE OVER THE
OHIO VALLEY AND MID ATLANTIC REGION NOSES INTO THE REGION. SKIES
WILL BE PARTLY TO MOSTLY SUNNY AND TEMPS LOOK WARM IN THE 80S. IT
WILL BE NOTICEABLY LESS HUMID AS WELL WITH DEWPOINTS ONLY IN THE
50S AS WELL.
AN UPPER LEVEL DISTURBANCE WILL START APPROACHING THE AREA FOR
FRIDAY NIGHT. IT SHOULD REMAIN DRY FOR MOST AREAS...ALTHOUGH
CANNOT RULE OUT A SHOWER OVER THE ADIRONDACKS FOR LATE FRI NIGHT.
MIN TEMPS LOOK TO BE IN THE MID 50S TO MID 60S.
SHORTWAVE TROUGH WILL BE SITUATED OVER THE NORTHEAST FOR SATURDAY
WITH A SFC FRONTAL BOUNDARY MOVING ACROSS THE AREA AS WELL. THERE
WILL BE A CHANCE FOR SHOWERS AND THUNDERSTORMS DURING THE DAY WITH
THE PASSAGE OF THIS BOUNDARY...ESP FOR NORTHERN AREAS. HIGHS TEMPS
LOOK TO BE IN THE 80S...WITH SOME 70S OVER THE HIGHER ELEVATIONS.
INSTABILITY MAY BE SOMEWHAT LIMITED TO CLOUDS AROUND AND TIMING
OF THE FRONT MAY NOT BE IDEAL FOR SEVERE STORMS TO OCCUR...ALTHOUGH
WILL CONTINUE TO MONITOR MODEL TRENDS.
THE SHORTWAVE SHOULD BE MOVING AWAY FOR SAT NIGHT...SO CLEARING
LOOKS TO OCCUR WITH ANY SHOWERS/THUNDERSTORMS ENDING DURING THE
EVENING HOURS. TEMPS LOOK TO FALL IN THE MID 50S TO LOW 60S
ACROSS THE REGION.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
IT STILL LOOKS AS IF A LONG WAVE TROUGH WILL BE DEVELOPING DURING
THE EXTENDED PERIOD OVER THE EASTERN CONUS. THIS DEEPENING TROUGH
WILL COMPROMISE OF A SERIES OF SHORT WAVES...DIVING FROM CENTRAL
CANADA TO THE MID ATLANTIC REGION. THE SPECIFIC TIMING OF THESE
SHORT WAVES IS DIFFICULT AT THIS TIME.
SUNDAY...THE FIRST OF THESE SHORT WAVES AND ASSOCIATED FRONTAL
BOUNDARY WILL BRUSH OUR REGION LATE INTO THE DAY AND EARLY EVENING
(MAINLY STAYING NORTH OF FORECAST AREA). WE KEPT SLIGHT TO LOW
CHANCES FROM THE CAPITAL REGION NORTHWESTWARD...NO POPS SOUTHEAST OF
THE CAPITAL REGION.
A STRONGER DISTURBANCE AND EVENTUALLY COLD FRONT IS FORECAST TO
APPROACH ON MONDAY OR MONDAY NIGHT. THIS COULD PACK MORE OF PUNCH
WITH MORE IN THE WAY OF SCATTERED SHOWERS AND THUNDERSTORMS ACROSS
MOST AREAS BY MONDAY NIGHT.
IT LOOKS AS IF PUSH OF SIGNIFICANTLY COOLER AIR WILL INFILTRATE
BEHIND THE COLD FRONT (OR SERIES OF COLD FRONTS) LATE TUESDAY AS
H850 TEMPERATURES LOOK TO GET PUSHED FROM TYPICAL MID TEENS VALUES
OF EARLY AUGUST...TO ABOUT +6C! THIS COOLING WILL PRODUCE INCREASED
LOW LEVEL INSTABILITY WHICH COULD TRIGGER SOME ADDITIONAL SHOWERS AND
PERHAPS A THUNDERSTORM ON TUESDAY INTO TUESDAY EVENING.
WEDNESDAY WILL BE NOTICEABLY COOLER AND WITH THE COLD POOL
ALOFT...THERE STILL COULD BE ADDITIONAL INSTABILITY SHOWERS...MAINLY
ACROSS THE ADIRONDACKS.
BY THURSDAY THE 12Z ECMWF STILL INDICATED A WAVE ALONG THE FRONT
ACROSS THE MID ATLANTIC REGION...PRODUCING A BAND OF RAIN ACROSS
MAINLY OUR SOUTHERN AREAS. THIS IDEA IS NOT SUPPORTED BY THE 12Z GFS
SO FOR NOW...ONLY INCLUDED A 20 PERCENT CHANCE OF SHOWERS (SLIGHT).
HIGH TEMPERATURES WILL START OUT WITH SEASONABLE READINGS FROM THE
UPPER 70S TO MID 80S ACROSS MOST OF OUR AREA SUNDAY THROUGH TUESDAY
WITH LOWS RANGING FROM MID 50S TO MID 60S. HOWEVER...BY WEDNESDAY
AND THURSDAY...HIGH TEMPERATURES WILL ONLY RANGE FROM THE UPPER 60S
ACROSS THE ADIRONDACKS...TO 70S ACROSS MOST OF THE REMAINDER OF THE
REGION. LOWS WILL DIP INTO THE 50S...WITH SOME UPPER 40S IN THE
COOLEST SPOTS WELL AWAY FROM THE HUDSON VALLEY.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
BROAD AREA OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS WAS MAKING
ITS WAY SOUTHEAST ACROSS KGFL AND KALB AT 1730Z. EXPECTING ACTIVITY
TO CLEAR OUT OF THESE TWO AIRPORTS AROUND 18Z...PUT POPCORN SHOWERS
WILL LINGER WITH WHAT LEFTOVER DAYTIME HEATING INTERACTS WITH SLOWLY-
DEPARTING MOISTURE AT THE LOW AND MID LEVELS...CARRYING JUST VCSH
FOR THIS.
AT KPSF...AND PARTICULARLY AT KPOU...THUNDERSTORMS STARTING
SHORTLY AFTER 18Z AS CELLS WITHIN RAIN AREA GAIN A LITTLE
STRENGTH...SHOULD LAST TIL 20Z. COLD FRONT LAGS BEHIND A COUPLE OF
HOURS...THEN THINGS IMPROVE MORE...ESPECIALLY AROUND
SUNSET...UNTIL MVFR/IFR FOG DEVELOPS AT THE AIRPORTS DURING THE
LATE OVERNIGHT.
WINDS WILL PICK UP BRIEFLY BEHIND THE FRONT...WITH LIGHT WINDS THEN
ALLOWING FOR THE FOG...WHICH WILL BURN OFF QUICKLY AFTER SUNRISE DUE
TO LACK OF CLOUD COVER AND EARLY MIXING. THROUGH THE COLUMN...SPEED
SHEAR IS JUST ENOUGH AT KGFL AND KALB TO INCLUDE WS FOR THE EVENING/
OVERNIGHT PERIOD.
OUTLOOK...
FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS OVER THE NEXT FEW DAYS. MANY AREAS SAW A
WETTING RAINFALL ON THURSDAY. A FEW MORE LINGERING SHOWERS OR
THUNDERSTORMS ARE POSSIBLE OVER SOUTHERN AREAS THIS
EVENING...OTHERWISE DRY WEATHER LOOKS TO RETURN FOR TONIGHT
THROUGH TOMORROW NIGHT. SOME SHOWERS OR THUNDERSTORMS ARE POSSIBLE
OVER THE WEEKEND.
AFTER RH VALUES RETURN TO NEAR 100 PERCENT TONIGHT...THEY ARE
EXPECTED TO DROP TO 35 TO 45 PERCENT ON FRIDAY AFTERNOON WITH WEST
WINDS OF 10 TO 15 MPH. RH VALUES LOOK TO RETURN TO AROUND 100
PERCENT ON FRI NIGHT. RH VALUES WILL DROP TO 40 TO 50 PERCENT ON
SAT AFTN WITH S-SW WINDS AT 5 TO 10 MPH.
&&
.HYDROLOGY...
NO MAIN STEM RIVER FLOODING IS FORECAST THROUGH THE NEXT FIVE DAYS.
WITH A COLD FRONT MOVING ACROSS THE REGION...SOME LINGERING
SHOWERS OR THUNDERSTORMS ARE ONGOING OVER THE MID HUDSON VALLEY
AND WESTERN NEW ENGLAND FOR THE LATE AFTN THROUGH THE EARLY
EVENING HOURS. WITH A HUMID AIR MASS IN PLACE...AND THE SHOWERS
AND THUNDERSTORMS MOVING RATHER SLOWLY...LOCALLY HEAVY DOWNPOURS
MAY ALLOW FOR SOME MINOR FLOODING OF URBAN OR POOR DRAINAGE AREAS.
ISOLATED FLASH FLOODING IS POSSIBLE OVER THE NEXT FEW HOURS...BUT
IS NOT EXPECTED TO BE WIDESPREAD...AS THE BOUNDARY SHOULD BE
CROSSING THE ENTIRE AREA SOON.
MAINLY DRY WEATHER WILL RETURN FOR TONIGHT THROUGH FRIDAY NIGHT.
SOME ADDITIONAL SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE
FOR SATURDAY INTO EARLY NEXT WEEK. WIDESPREAD HEAVY RAIN ISN/T
EXPECTED...BUT ANY THUNDERSTORM IS CAPABLE OF PRODUCING LOCALLY
HEAVY DOWNPOURS.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS
SHORT TERM...FRUGIS
LONG TERM...HWJIV
AVIATION...ELH
FIRE WEATHER...FRUGIS
HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
353 PM EDT THU JUL 30 2015
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING WILL GIVE WAY
TO DRIER WEATHER FRIDAY...BUT IT WILL REMAIN VERY WARM. WARM AND
HUMID CONDITIONS WILL RETURN THIS WEEKEND...THEN WILL BECOME LESS
HUMID WITH TEMPERATURES CLOSER TO NORMAL NEXT WEEK. THERE IS A LOW
RISK FOR SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THIS WEEKEND
INTO EARLY NEXT WEEK...HOWEVER MUCH OF THE TIME DRY WEATHER WILL
PREVAIL.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
355 PM UPDATE...
* LINE OF STRONG TO POSSIBLY SEVERE STORMS THRU 9 PM *
* LOCALIZED WIND DAMAGE/FLOODING AND PERHAPS AN ISOLATED TORNADO
MESOANALYSIS SHOWS 1500-2000 K/KG OF SB CAPE ACROSS SOUTHERN NEW
ENGLAND WITH 25KT OF 0-6KM SHEAR BUT MEAGER MID LEVEL LAPSE RATES.
LINE OF STORMS HAS BECOME MORE ORGANIZED FROM SW MA ACROSS CT AND
INTO NYC AREA. SO FAR HEAVY RAIN HAS BEEN MAIN THREAT BUT
OCCASIONALLY WE HAVE SEEN HIGHER CORES DEVELOP IN SOME OF THE
STORMS...SO POTENTIAL FOR LOCALIZED WIND DAMAGE AND FLOODING WILL
CONTINUE INTO THIS EVENING.
FOCUS FOR STORMS LOOKS TO BE ACROSS CT...NORTHERN RI AND CENTRAL/
EASTERN MA PER HIGH-RES MODELS. IN PARTICULAR HRRR SHOWS EVOLUTION
NICELY ALTHOUGH ITS TIMING IS A COUPLE OF HOURS TOO SLOW. LINE
SHOULD REACH PROVIDENCE/BOSTON CORRIDOR 6-7 PM.
ALTHOUGH VERY LOW PROBABILITY...STILL CANNOT RULE OUT AN ISOLATED
TORNADO PRIMARILY AS FAR E AS WORCESTER HILLS. PRESENCE OF
30-35KT WINDS AT 925 MB AND LOW LCL FROM 70+ DEWPOINTS POINTS
TOWARD THAT POTENTIAL. IF ONE DOES OCCUR... AND THAT IS A BIG
IF...IT WOULD LIKELY BE TOWARD WEAKER SIDE GIVEN STRENGTH OF WIND
FIELDS ALOFT.
ACTIVITY DIMINISHES TONIGHT WITH LOSS OF DAYTIME HEATING AND
PASSAGE OF COLD FRONT. EXPECT PATCHY FOG TO DEVELOP OVERNIGHT.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
FRONT WILL BE OFFSHORE FRI MORNING WITH DRIER AND MORE COMFORTABLE
AIRMASS IN ITS WAKE. KEEPING FRI NIGHT DRY ALTHOUGH WE SHOULD SEE
INCREASING CLOUDS AS NEXT SHORT WAVE APPROACHES.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
HIGHLIGHTS...
* EXPECT MORE SEASONABLE TEMPS AND LOWER HUMIDITY THROUGH MOST OF
THIS PERIOD
* CHANCE FOR A FEW SHOWERS/ISOLATED THUNDER EACH DAY BUT MUCH OF THE
TIME REMAINING DRY
SYNOPTIC OVERVIEW AND MODEL PREFERENCES...
MEDIUM RANGE FORECAST CONTINUES TO FEATURE ANOMALOUS H5 CUTOFF
VORTEX ACROSS JAMES AND HUDSON BAYS WHICH WILL ELONGATE ACROSS
QUEBEC DURING THE LONG TERM PERIOD. WILL STILL SEE LONG WAVE TROUGH
ACROSS THE EASTERN GREAT LAKES AND DOWN THE APPALACHIANS WHICH WILL
TEND TO FLATTEN...THOUGH SHORT WAVES WILL ROTATE AROUND THE BASE OF
THE CUTOFF LOW INTO THE MEAN TROUGH. THIS WILL BRING PERIODS OF
SHOWERS/THUNDERSTORMS ACROSS THE REGION FROM TIME TO TIME. NOT
EXPECTED A TOTAL WASHOUT AT ANY TIME...THOUGH MODELS LOOK LIKE THEY
MAY HAVE SOME CONTINUITY WILL BE AROUND THE LATE MON/MON NIGHT AND
TUE NIGHT TIMEFRAMES. HOWEVER...OPERATIONAL MODEL SOLUTION SPREAD
DOES WIDENS OVER TIME AS ONE WOULD EXPECT ESPECIALLY THIS TIME OF
THE YEAR...SO CONFIDENCE IN SPECIFIC TIMING OF CONVECTION AND ANY
SHORT WAVE PASSAGE LOWERS.
USED A BLEND OF AVAILABLE GUIDANCE INTO MONDAY...THEN TRANSITIONED
OVER TO THE GFS AND EC ENS MEANS WHICH GAVE A BIT MORE CONTINUITY
WITH PREVIOUS FORECASTS.
DETAILS...
SATURDAY...MODELS CONTINUE TO PAINT A WEAK H5 SHORT WAVE IN THE MEAN
UPPER FLOW FOR LATER SAT INTO SAT NIGHT. LOOKS LIKE BEST INSTABILITY
AND MOISTURE...WHAT THERE IS OF IT...WILL BE ACROSS CENTRAL AND
WESTERN AREAS. ANOTHER QUESTION WILL BE WHETHER THERE WILL BE SOME
NOCTURNAL INSTABILITY SHOWERS/TSTMS ALONG THE S COAST WHERE HIGHEST
HUMIDITIES ARE IN PLACE. HAVE LEFT OUT FOR NOW...BUT IT IS SIGNALED
ON THE GFS MODEL.
HAVE GENERALLY SLIGHT CHANCE POPS GOING...BUT MAY SEE A LINE OF SCT
SHOWERS/TSTMS ACROSS CT VALLEY INTO CENTRAL MA/NE CT POSSIBLE DURING
THE LATE AFTERNOON/EARLY EVENING. EXPECT THE SHORT WAVE TO SHIFT E
AND WEAKEN SO PRECIP SHOULD ALSO WEAKEN OVERNIGHT.
HIGHS WILL GENERALLY BE IN THE 80S. IT WILL BE COOLER WELL INLAND
LATE SAT NIGHT WITH LOWS AROUND 60...RANGING TO AROUND 70 ALONG THE
S COAST...CAPE COD AND THE ISLANDS.
SUNDAY...WEAK SURFACE RIDGE BUILDS ACROSS SO EXPECT A MAINLY DRY
DAY. H85 TEMPS WILL BE FROM +15C TO +16C...WHICH WILL TRANSLATE TO
THE 80S FOR MOST AREAS...A BIT COOLER ALONG THE S COAST WITH THE S-
SW WINDS IN PLACE.
MONDAY...SOUTHWEST WIND FLOW REMAINS IN PLACE. MODELS SIGNALING A
POSSIBLE PRE FRONTAL TROUGH APPROACHING LATE MON OR MON NIGHT
/TIMING IN QUESTION/. MAY SEE WIDELY SCT SHOWERS/ISOLD TSTMS ACROSS
CENTRAL AND WESTERN AREAS...WITH THE BEST CHANCE ACROSS W MA AND W
HARTFORD COUNTY. WITH THE MILDER S-SW FLOW IN PLACE...EXPECT HIGHS
MAINLY IN THE 80S.
TUESDAY...W-SW FLOW ALOFT AS QUEBEC VORTEX BROADENS. ANOTHER SHORT
WAVE AND ASSOCIATED COLD FRONT LOOKS TO APPROACH LATE TUE INTO TUE
EVENING. GFS MOST AGGRESSIVE IN DIGGING H5 TROUGH TO THE W WHICH
WILL KEEP WARM AND HUMID AIR IN PLACE. HAVE CARRIED CHANCE POPS
ACROSS THE REGION...THEN SHOULD PUSH OFFSHORE TUE NIGHT.
WEDNESDAY-THURSDAY...A LOT OF QUESTIONS AS TO WHETHER FRONT WILL
STALL S OF NEW ENGLAND DURING THIS TIMEFRAME AND IF WAVES WILL MOVE
ALONG THIS FRONT. FOR NOW...HAVE CHANCE POPS MOVING ACROSS WED
NIGHT/THU...BUT TIMING IS STILL VERY MUCH IN QUESTION. LOW
CONFIDENCE DURING THIS TIMEFRAME DUE TO TIMING DIFFERENCES.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
HIGH CONFIDENCE THROUGH FRI NIGHT.
LINE OF SHOWERS/TSTMS WITH MVFR/IFR ARRIVE IN W NEW ENGLAND 18Z-
20Z AND SHOULD WEAKEN BEFORE REACHING COAST 21Z- 00Z. HEAVY RAIN
MAIN THREAT BUT POTENTIAL FOR 40-50KT GUSTS IN STRONGER STORMS. SW
WINDS GUST TO 25KT ESPECIALLY NEAR S COAST.
MVFR/IFR CIGS SHOULD RETURN TO PARTS OF A COAST...CAPE COD AND
ISLANDS THIS EVENING. COULD ALSO SEE PATCHY IFR DUE TO VALLEY FOG
INLAND. VFR FRI AND FRI NIGHT WITH W/SW WINDS...MAY HAVE LOCAL
SEA BREEZES DURING AFTERNOON NEAR COAST.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. MAIN WINDOW FOR TSTMS
22Z-00Z. HEAVY RAIN/LIGHTNING MAIN HAZARDS.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF. MAIN WINDOW FOR TSTMS
THRU 21Z. 40KT GUSTS POSSIBLE IN STRONGER STORMS.
OUTLOOK /SATURDAY THROUGH TUESDAY/...MODERATE CONFIDENCE.
EXPECT GENERALLY VFR MOST OF THE TIME. LOW CHANCE OF SCT SHOWERS/
ISOLD THUNDERSTORMS SAT AFTERNOON/EARLY SAT NIGHT AND AGAIN MON-TUE.
BRIEF LOCAL MVFR IN ANY PRECIP.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
HIGH CONFIDENCE THROUGH FRI NIGHT.
SCA REMAINS POSTED FOR 20-30KT GUSTS THIS AFTERNOON NEAR SHORE AS
GRADIENT TIGHTENS AHEAD OF COLD FRONT. IN ADDITION...LONG
SOUTHWEST FETCH WILL ALLOW FOR SEAS TO BUILD TO BETWEEN 3 TO 5
FEET ACROSS MOST OPEN WATERS. WINDS DIMINISH THIS EVENING...BUT
KEEPING SCA THROUGH TONIGHT FOR THE OUTER WATERS DUE TO LEFTOVER
SWELL.
HIGH PRESSURE WILL BUILD OVER REGION FRI AND FRI NIGHT WITH LIGHT
WINDS AND DIMINISHING SEAS.
OUTLOOK /SATURDAY THROUGH TUESDAY/...
SATURDAY-SUNDAY...SW WINDS MAY GUST UP TO 20 KT SAT/SAT NIGHT THEN
DIMINISH. WITH LONG S-SW FETCH...SEAS FORECAST UP TO 5 FT MAINLY ON
THE SOUTHERN OUTER WATERS.
MONDAY-TUESDAY...CONTINUED SW WINDS IN PLACE...WHICH MAY GUST TO 20
KT AT TIMES. SEAS UP TO 5-7 FT ON THE SOUTHERN OUTER WATERS. MAY SEE
SCT SHOWERS/THUNDERSTORMS MON NIGHT/TUE.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR
ANZ230>234-236-251.
SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR ANZ235-
237.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT FRIDAY FOR ANZ250-254>256.
&&
$$
SYNOPSIS...EVT/JWD
NEAR TERM...JWD
SHORT TERM...JWD
LONG TERM...EVT
AVIATION...EVT/JWD
MARINE...EVT/JWD
AREA FORECAST DISCUSSION
NWS ALBANY NY
149 PM EDT THU JUL 30 2015
.SYNOPSIS...
WITH A COLD FRONT MOVING ACROSS THE REGION...SOME
SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO THE EARLY EVENING
HOURS. BEHIND THIS BOUNDARY...LESS HUMID AIR WILL MOVE INTO THE AREA
FOR TONIGHT INTO FRIDAY...ALTHOUGH TEMPERATURES WILL CONTINUE TO BE
WARM ON FRIDAY. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL RETURN
ON SATURDAY...WITH TEMPERATURES SLIGHTLY ABOVE NORMAL LEVELS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 133 PM EDT...BAND OF RAIN SHOWERS AND EMBEDDED THUNDER
EXTENDS FROM LAKE GEORGE DOWN THROUGH SARATOGA COUNTY AND INTO THE
CAPITAL REGION. FURTHER SOUTH...THE BAND IS NOT AS
CONTINUOUS...BUT SOME SHOWERS ARE IMPACTING THE EASTERN CATSKILLS
AND MID HUDSON VALLEY. ALL OF THIS ACTIVITY WILL CONTINUE TO
GRADUALLY SLIDE EASTWARD OVER THE NEXT FEW HOURS. THERE HAVE BEEN
SOME EMBEDDED HEAVIER BURSTS OF RAINFALL...ESP OVER SARATOGA
COUNTY IN THE BALLSTON SPA AND MALTA AREAS...WHERE DUAL POL RADAR
ESTIMATES AROUND UP TO AN INCH AND A HALF OF RAIN HAS FALLEN.
THE MAIN THREAT THIS AFTN LOOKS TO BE LOCALLY HEAVY RAINFALL...AS
BOTH INSTABILITY AND SHEAR PARAMETERS DON/T FAVOR MUCH IN THE WAY
OF SEVERE STORMS. SPC CONTINUES JUST A MARGINAL RISK FOR SEVERE
STORMS THROUGH THE AFTN HOURS. THE LATEST 3KM HRRR SUGGESTS THAT
THE CURRENT ACTIVITY WILL CONTINUE TO SLIDE EASTWARD INTO NEW
ENGLAND BY THE MID TO LATE AFTN HOURS.
AFTER THE MAIN BAND OF SHOWERS PASSES THROUGH...THE MAIN COLD
FRONT...NOW OVER CENTRAL NY...WILL STILL APPROACH AND MOVE
THROUGH FROM W TO E LATER THIS AFTERNOON/EARLY EVENING. IN
ADDITION...OUR REGION WILL BECOME CLOSER TO THE RIGHT ENTRANCE
REGION OF AN UPPER LEVEL JET MAX TRANSLATING ACROSS THE EASTERN
GREAT LAKES/SE CANADA LATER TODAY. DEPENDING ON HOW MUCH SUNSHINE
AND LOW LEVEL HEATING OCCURS IN THE WAKE OF THE MIDDAY
SHOWERS...WILL DETERMINE IF ADDITIONAL ISOLATED TO SCATTERED
CONVECTION DEVELOPS CLOSER TO OR ALONG THE FRONT LATER THIS
AFTERNOON. THIS POTENTIAL APPEARS GREATEST FOR AREAS MAINLY S AND
E OF ALBANY...ALTHOUGH STILL REMAINS LOW OVERALL.
PWATS ARE FORECAST TO SURGE AHEAD OF THE COLD FRONT TO +2 TO +3
STDEV ACCORDING TO THE GEFS. THUS SHOWERS/STORMS WILL BE CAPABLE
OF PRODUCING TORRENTIAL DOWNPOURS IN A SHORT AMOUNT OF TIME. SOME
MAINLY MINOR URBAN/POOR DRAINAGE FLOODING WILL BE POSSIBLE...AS
WELL AS ISOLATED FLASH FLOODING.
TEMPERATURES WILL CONTINUE TO BE VERY WARM...BUT COOLER THAN
WEDNESDAY DUE TO INCREASING CLOUDS AND CHANCES FOR SHOWERS/STORMS.
HUMIDITY LEVELS WILL BE HIGHER THOUGH...MAKING IT FEEL QUICK
MUGGY. TEMPS WILL LIKELY SPIKE AHEAD OF THE MAIN BAND OF MIDDAY
SHOWERS...IN THE LOWER/MID 80S IN VALLEY AND UPPER 70S TO NEAR 80
ACROSS HIGHER TERRAIN...THEN MAY DROP INTO THE 70S FOR A FEW HOURS
BEFORE RECOVERING BACK INTO THE UPPER 70S/LOWER 80S AGAIN LATER
THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
THE COLD FRONT SHOULD PUSH THROUGH WESTERN NEW ENGLAND EARLY THIS
EVENING...WITH SHOWERS AND THUNDERSTORMS ENDING THERE BY SUNSET.
AREAS TO THE WEST WILL BE DRY TO START THE EVENING WITH A WEST
WIND DEVELOPING BEHIND THE COLD FRONT. AS THE FRONT PUSHES WELL
EAST OF OUR REGION BY LATE EVENING...DRYING AND CLEARING WILL
OCCUR. TEMPERATURES WILL BE COOLER AND CLOSER TO NORMAL TONIGHT
WITH MAINLY UPPER 50S TO MID 60S FOR LOWS.
FRIDAY LOOKS TO BE A QUIET AND SEASONABLE DAY ACROSS THE REGION
AS A SURFACE RIDGE OF HIGH PRESSURE BUILDS IN FROM THE OHIO
VALLEY. JUST SOME FAIR WEATHER CU AND CIRRUS CLOUDS AROUND WITH
NOTICEABLY LESS HUMID CONDITIONS WITH DEWPOINTS IN THE 50S AND A
WESTERLY BREEZE. TEMPERATURES WILL STILL BE SLIGHTLY ABOVE NORMAL
IN MANY SPOTS BUT THE BREEZE AND LOWER HUMIDITY WILL MAKE IT FEEL
MUCH MORE COMFORTABLE.
UPPER LEVEL HEIGHTS WILL START TO GRADUALLY FALL FRIDAY
NIGHT...AS A BROAD TROUGH STARTS TO GET CARVED OUT OVER THE GREAT
LAKES. AN APPROACHING SHORT WAVE AND JET STREAK WILL BRING A LOW
CHANCE OF SHOWERS MAINLY FOR AREAS NORTH OF THE CAPITAL DISTRICT.
THIS DISTURBANCE WILL MOVE ACROSS THE REGION ON
SATURDAY...PROMOTING MAINLY SCATTERED SHOWERS AND THUNDERSTORMS.
TIMING STILL IN QUESTION REGARDING MAGNITUDE OF INSTABILITY...BUT
FOR NOW IT APPEARS AT LEAST GENERAL THUNDERSTORMS WILL OCCUR AS
CLOUDS MAY INCREASE FAIRLY QUICKLY SATURDAY MORNING INTO EARLY
AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE LONG TERM PERIOD WILL FEATURE A GRADUALLY DEEPENING LONG WAVE
TROF OVER THE EASTERN UNITED STATES...WITH MINOR DISTURBANCES
ROTATING AROUND THE LONG WAVE TROF AND THROUGH THE ALBANY FORECAST
AREA. THIS WILL RESULT IN AN UNSETTLED PERIOD OF WEATHER WITH SLIGHT
CHANCE TO CHANCE POPS FORECAST JUST ABOUT EVERY PERIOD FOR AT LEAST
SOME PART OF THE FORECAST AREA.. THE ONLY PERIOD THAT IS FORECAST
TO BE DRY FOR THE ENTIRE AREA IS TUESDAY NIGHT...AND THE PERIOD WITH
THE HIGHEST POPS FOR THE ENTIRE AREA (30 TO 40 PERCENT) IS MONDAY
NIGHT AND TUESDAY. THE REST OF THE TIME POPS WILL RANGE FROM DRY
OVER THE SOUTHEAST PART OF THE FORECAST AREA...TO LOW CHANCE POPS
OVER THE ADIRONDACKS...WHICH WILL BE CLOSEST TO INDIVIDUAL
DISTURBANCES ROTATING AROUND THE LONG WAVE TROF. IT SHOULD BE NOTED
THAT THE GFS AND ECMWF VARY WITH THE TIMING OF THESE DISTURBANCES...
SO CONFIDENCE IN THE FORECAST FROM DAY TO DAY IS FAIRLY LOW SINCE
THE TIMING OF THESE SYSTEMS WILL LIKELY CHANGE WITH FUTURE MODEL RUNS.
TEMPERATURE WISE THE LONG TERM PERIOD WILL START OUT A LITTLE ABOVE
NORMAL...WITH A GRADUAL COOL DOWN LATER IN THE PERIOD AS THE LONG
WAVE TROF DEEPENS OVER THE REGION. SPECIFICALLY...LOWS SATURDAY NIGHT
WILL BE IN THE MID 50S TO LOWER 60S. HIGHS SUNDAY GENERALLY IN THE
MID 70S TO MID 80S. LOWS SUNDAY NIGHT IN THE MID 50S TO MID 60S.
HIGHS MONDAY IN THE UPPER 70S AND 80S. LOWS MONDAY NIGHT IN THE MID
50S TO MID 60S. HIGHS TUESDAY IN THE MID 70S TO MID 80S. LOWS
TUESDAY NIGHT IN THE 50S AND LOWER 60S. HIGHS WEDNESDAY IN THE 70S
TO MID 80S...WITH SOME UPPER 60S OVER THE ADIRONDACKS.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
BROAD AREA OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS WAS MAKING
ITS WAY SOUTHEAST ACROSS KGFL AND KALB AT 1730Z. EXPECTING ACTIVITY
TO CLEAR OUT OF THESE TWO AIRPORTS AROUND 18Z...PUT POPCORN SHOWERS
WILL LINGER WITH WHAT LEFTOVER DAYTIME HEATING INTERACTS WITH SLOWLY-
DEPARTING MOISTURE AT THE LOW AND MID LEVELS...CARRYING JUST VCSH
FOR THIS.
AT KPSM...AND PARTICULARLY AT KPOU...THUNDERSTORMS STARTING SHORTLY
AFTER 18Z AS CELLS WITHIN RAIN AREA GAIN A LITTLE STRENGTH...SHOULD
LAST TIL 20Z. COLD FRONT LAGS BEHIND A COUPLE OF HOURS...THEN
THINGS IMPROVE MORE...ESPECIALLY AROUND SUNSET...UNTIL MVFR/IFR FOG
DEVELOPS AT THE AIRPORTS DURING THE LATE OVERNIGHT.
WINDS WILL PICK UP BRIEFLY BEHIND THE FRONT...WITH LIGHT WINDS THEN
ALLOWING FOR THE FOG...WHICH WILL BURN OFF QUICKLY AFTER SUNRISE DUE
TO LACK OF CLOUD COVER AND EARLY MIXING. THROUGH THE COLUMN...SPEED
SHEAR IS JUST ENOUGH AT KGFL AND KALB TO INCLUDE WS FOR THE EVENING/
OVERNIGHT PERIOD.
OUTLOOK...
FRIDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
A COLD FRONT APPROACHING FROM WESTERN NEW YORK WILL RESULT IN
SHOWERS AND THUNDERSTORMS ACROSS THE REGION TODAY...AS THE FRONT
PROGRESSES EASTWARD. IT WILL REMAIN WARM AND MUGGY THROUGH MUCH OF
TODAY AHEAD OF THE COLD FRONT. BEHIND THE COLD FRONT...COOLER AND
DRIER AIR WILL FILTER INTO THE REGION TONIGHT INTO FRIDAY.
TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL INTO THE WEEKEND. CHANCES
FOR SHOWERS AND THUNDERSTORMS WILL INCREASE AGAIN ON SATURDAY...AS
AN UPPER LEVEL DISTURBANCE MOVES ACROSS THE REGION.
MINIMUM RELATIVE HUMIDITY VALUES THIS AFTERNOON ARE EXPECTED TO BE
BETWEEN 50 AND 60 PERCENT...INCREASING TO MAXIMUM VALUES OF 90 TO
100 PERCENT TONIGHT. MIN RH VALUES FRIDAY WILL DROP TO AROUND 35 TO
50 PERCENT DURING THE AFTERNOON.
WINDS TODAY WILL BE SOUTH-SOUTHWEST AROUND 5 TO 10 MPH...BECOMING
SOUTHWEST AROUND 5 MPH TONIGHT. WINDS ON FRIDAY WILL BE WESTERLY AT
5 TO 15 MPH.
&&
.HYDROLOGY...
NO MAIN STEM RIVER FLOODING IS FORECAST THROUGH THE NEXT 5 DAYS.
FAIRLY WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY AS A
COLD FRONT CROSS THE AREA. WITH PWAT VALUES POTENTIALLY NEAR TWO
INCHES...THUNDERSTORMS WILL BE CAPABLE OF PRODUCING VERY HEAVY
RAINFALL...WHICH MAY CAUSE LOCALIZED MINOR FLOODING OF URBAN...LOW
LYING AND POOR DRAINAGE AREAS. ISOLATED FLASH FLOODING CANNOT BE
RULED OUT...BUT THE THREAT WILL NOT BE WIDESPREAD.
MAINLY DRY WEATHER WILL RETURN FOR TONIGHT THROUGH FRIDAY NIGHT.
SOME ADDITIONAL SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE
MAINLY DURING THE FIRST HALF OF THE WEEKEND.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS/KL/JPV
SHORT TERM...JPV
LONG TERM...GJM
AVIATION...ELH
FIRE WEATHER...JPV
HYDROLOGY...FRUGIS/JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
133 PM EDT THU JUL 30 2015
.SYNOPSIS...
WITH A COLD FRONT MOVING ACROSS THE REGION...SOME
SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO THE EARLY EVENING
HOURS. BEHIND THIS BOUNDARY...LESS HUMID AIR WILL MOVE INTO THE AREA
FOR TONIGHT INTO FRIDAY...ALTHOUGH TEMPERATURES WILL CONTINUE TO BE
WARM ON FRIDAY. THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL RETURN
ON SATURDAY...WITH TEMPERATURES SLIGHTLY ABOVE NORMAL LEVELS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 133 PM EDT...BAND OF RAIN SHOWERS AND EMBEDDED THUNDER
EXTENDS FROM LAKE GEORGE DOWN THROUGH SARATOGA COUNTY AND INTO THE
CAPITAL REGION. FURTHER SOUTH...THE BAND IS NOT AS
CONTINUOUS...BUT SOME SHOWERS ARE IMPACTING THE EASTERN CATSKILLS
AND MID HUDSON VALLEY. ALL OF THIS ACTIVITY WILL CONTINUE TO
GRADUALLY SLIDE EASTWARD OVER THE NEXT FEW HOURS. THERE HAVE BEEN
SOME EMBEDDED HEAVIER BURSTS OF RAINFALL...ESP OVER SARATOGA
COUNTY IN THE BALLSTON SPA AND MALTA AREAS...WHERE DUAL POL RADAR
ESTIMATES AROUND UP TO AN INCH AND A HALF OF RAIN HAS FALLEN.
THE MAIN THREAT THIS AFTN LOOKS TO BE LOCALLY HEAVY RAINFALL...AS
BOTH INSTABILITY AND SHEAR PARAMETERS DON/T FAVOR MUCH IN THE WAY
OF SEVERE STORMS. SPC CONTINUES JUST A MARGINAL RISK FOR SEVERE
STORMS THROUGH THE AFTN HOURS. THE LATEST 3KM HRRR SUGGESTS THAT
THE CURRENT ACTIVITY WILL CONTINUE TO SLIDE EASTWARD INTO NEW
ENGLAND BY THE MID TO LATE AFTN HOURS.
AFTER THE MAIN BAND OF SHOWERS PASSES THROUGH...THE MAIN COLD
FRONT...NOW OVER CENTRAL NY...WILL STILL APPROACH AND MOVE
THROUGH FROM W TO E LATER THIS AFTERNOON/EARLY EVENING. IN
ADDITION...OUR REGION WILL BECOME CLOSER TO THE RIGHT ENTRANCE
REGION OF AN UPPER LEVEL JET MAX TRANSLATING ACROSS THE EASTERN
GREAT LAKES/SE CANADA LATER TODAY. DEPENDING ON HOW MUCH SUNSHINE
AND LOW LEVEL HEATING OCCURS IN THE WAKE OF THE MIDDAY
SHOWERS...WILL DETERMINE IF ADDITIONAL ISOLATED TO SCATTERED
CONVECTION DEVELOPS CLOSER TO OR ALONG THE FRONT LATER THIS
AFTERNOON. THIS POTENTIAL APPEARS GREATEST FOR AREAS MAINLY S AND
E OF ALBANY...ALTHOUGH STILL REMAINS LOW OVERALL.
PWATS ARE FORECAST TO SURGE AHEAD OF THE COLD FRONT TO +2 TO +3
STDEV ACCORDING TO THE GEFS. THUS SHOWERS/STORMS WILL BE CAPABLE
OF PRODUCING TORRENTIAL DOWNPOURS IN A SHORT AMOUNT OF TIME. SOME
MAINLY MINOR URBAN/POOR DRAINAGE FLOODING WILL BE POSSIBLE...AS
WELL AS ISOLATED FLASH FLOODING.
TEMPERATURES WILL CONTINUE TO BE VERY WARM...BUT COOLER THAN
WEDNESDAY DUE TO INCREASING CLOUDS AND CHANCES FOR SHOWERS/STORMS.
HUMIDITY LEVELS WILL BE HIGHER THOUGH...MAKING IT FEEL QUICK
MUGGY. TEMPS WILL LIKELY SPIKE AHEAD OF THE MAIN BAND OF MIDDAY
SHOWERS...IN THE LOWER/MID 80S IN VALLEY AND UPPER 70S TO NEAR 80
ACROSS HIGHER TERRAIN...THEN MAY DROP INTO THE 70S FOR A FEW HOURS
BEFORE RECOVERING BACK INTO THE UPPER 70S/LOWER 80S AGAIN LATER
THIS AFTERNOON.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
THE COLD FRONT SHOULD PUSH THROUGH WESTERN NEW ENGLAND EARLY THIS
EVENING...WITH SHOWERS AND THUNDERSTORMS ENDING THERE BY SUNSET.
AREAS TO THE WEST WILL BE DRY TO START THE EVENING WITH A WEST
WIND DEVELOPING BEHIND THE COLD FRONT. AS THE FRONT PUSHES WELL
EAST OF OUR REGION BY LATE EVENING...DRYING AND CLEARING WILL
OCCUR. TEMPERATURES WILL BE COOLER AND CLOSER TO NORMAL TONIGHT
WITH MAINLY UPPER 50S TO MID 60S FOR LOWS.
FRIDAY LOOKS TO BE A QUIET AND SEASONABLE DAY ACROSS THE REGION
AS A SURFACE RIDGE OF HIGH PRESSURE BUILDS IN FROM THE OHIO
VALLEY. JUST SOME FAIR WEATHER CU AND CIRRUS CLOUDS AROUND WITH
NOTICEABLY LESS HUMID CONDITIONS WITH DEWPOINTS IN THE 50S AND A
WESTERLY BREEZE. TEMPERATURES WILL STILL BE SLIGHTLY ABOVE NORMAL
IN MANY SPOTS BUT THE BREEZE AND LOWER HUMIDITY WILL MAKE IT FEEL
MUCH MORE COMFORTABLE.
UPPER LEVEL HEIGHTS WILL START TO GRADUALLY FALL FRIDAY
NIGHT...AS A BROAD TROUGH STARTS TO GET CARVED OUT OVER THE GREAT
LAKES. AN APPROACHING SHORT WAVE AND JET STREAK WILL BRING A LOW
CHANCE OF SHOWERS MAINLY FOR AREAS NORTH OF THE CAPITAL DISTRICT.
THIS DISTURBANCE WILL MOVE ACROSS THE REGION ON
SATURDAY...PROMOTING MAINLY SCATTERED SHOWERS AND THUNDERSTORMS.
TIMING STILL IN QUESTION REGARDING MAGNITUDE OF INSTABILITY...BUT
FOR NOW IT APPEARS AT LEAST GENERAL THUNDERSTORMS WILL OCCUR AS
CLOUDS MAY INCREASE FAIRLY QUICKLY SATURDAY MORNING INTO EARLY
AFTERNOON.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
THE LONG TERM PERIOD WILL FEATURE A GRADUALLY DEEPENING LONG WAVE
TROF OVER THE EASTERN UNITED STATES...WITH MINOR DISTURBANCES
ROTATING AROUND THE LONG WAVE TROF AND THROUGH THE ALBANY FORECAST
AREA. THIS WILL RESULT IN AN UNSETTLED PERIOD OF WEATHER WITH SLIGHT
CHANCE TO CHANCE POPS FORECAST JUST ABOUT EVERY PERIOD FOR AT LEAST
SOME PART OF THE FORECAST AREA.. THE ONLY PERIOD THAT IS FORECAST
TO BE DRY FOR THE ENTIRE AREA IS TUESDAY NIGHT...AND THE PERIOD WITH
THE HIGHEST POPS FOR THE ENTIRE AREA (30 TO 40 PERCENT) IS MONDAY
NIGHT AND TUESDAY. THE REST OF THE TIME POPS WILL RANGE FROM DRY
OVER THE SOUTHEAST PART OF THE FORECAST AREA...TO LOW CHANCE POPS
OVER THE ADIRONDACKS...WHICH WILL BE CLOSEST TO INDIVIDUAL
DISTURBANCES ROTATING AROUND THE LONG WAVE TROF. IT SHOULD BE NOTED
THAT THE GFS AND ECMWF VARY WITH THE TIMING OF THESE DISTURBANCES...
SO CONFIDENCE IN THE FORECAST FROM DAY TO DAY IS FAIRLY LOW SINCE
THE TIMING OF THESE SYSTEMS WILL LIKELY CHANGE WITH FUTURE MODEL RUNS.
TEMPERATURE WISE THE LONG TERM PERIOD WILL START OUT A LITTLE ABOVE
NORMAL...WITH A GRADUAL COOL DOWN LATER IN THE PERIOD AS THE LONG
WAVE TROF DEEPENS OVER THE REGION. SPECIFICALLY...LOWS SATURDAY NIGHT
WILL BE IN THE MID 50S TO LOWER 60S. HIGHS SUNDAY GENERALLY IN THE
MID 70S TO MID 80S. LOWS SUNDAY NIGHT IN THE MID 50S TO MID 60S.
HIGHS MONDAY IN THE UPPER 70S AND 80S. LOWS MONDAY NIGHT IN THE MID
50S TO MID 60S. HIGHS TUESDAY IN THE MID 70S TO MID 80S. LOWS
TUESDAY NIGHT IN THE 50S AND LOWER 60S. HIGHS WEDNESDAY IN THE 70S
TO MID 80S...WITH SOME UPPER 60S OVER THE ADIRONDACKS.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
A COLD FRONT WILL MOVE ACROSS THE REGION DURING THE AFTERNOON...
ACCOMPANIED BY SOME SHOWERS AND THUNDERSTORMS.
EXCEPT FOR MVFR CIGS AT KPOU...EXPECT MAINLY VFR CONDITIONS AT
THE KALB/KGFL/KPOU/KPSF TAF SITES UNTIL THE COLD FRONT APPROACHES.
THE COLD FRONT WILL MOVE ACROSS THE REGION THIS AFTERNOON...AND
HAVE GENERALLY FORECAST A 3-4 HOUR PERIOD OF SHOWERS AT ALL THE
TAF SITES. WILL ALSO INCLUDE MENTION OF VCTS...AS SOME EMBEDDED
THUNDERSTORMS WILL BE POSSIBLE. AT KGFL THE WINDOW FOR
SHOWERS/POSSIBLE TSTMS IS FROM 16Z-18Z...KALB 17Z- 19Z...KPSF AND
KPOU 19Z- 21Z.
AFTER THE COLD FRONT MOVES THROUGH AND ANY CONVECTIVE ACTIVITY
ENDS...EXPECT VFR CONDITIONS TO RETURN TO ALL THE TAF SITES...BUT
MVFR/IFR CONDITIONS POSSIBLE LATE TONIGHT DUE TO THE POSSIBILITY
OF FOG FORMATION.
SURFACE WINDS WILL BE SOUTH TO SOUTHWEST 5 TO 10 KTS EARLY TODAY.
AFTER THE FRONT MOVES THROUGH...WINDS WILL BECOME WEST TO
SOUTHWEST. AFTER SUNSET...WINDS WILL BECOME LIGHT AND VARIABLE.
WINDS WILL BE MUCH STRONGER...AND VARIABLE IN DIRECTION IN AND
NEAR ANY THUNDERSTORMS.
OUTLOOK...
FRIDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
SATURDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUNDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
MONDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
&&
.FIRE WEATHER...
A COLD FRONT APPROACHING FROM WESTERN NEW YORK WILL RESULT IN
SHOWERS AND THUNDERSTORMS ACROSS THE REGION TODAY...AS THE FRONT
PROGRESSES EASTWARD. IT WILL REMAIN WARM AND MUGGY THROUGH MUCH OF
TODAY AHEAD OF THE COLD FRONT. BEHIND THE COLD FRONT...COOLER AND
DRIER AIR WILL FILTER INTO THE REGION TONIGHT INTO FRIDAY.
TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL INTO THE WEEKEND. CHANCES
FOR SHOWERS AND THUNDERSTORMS WILL INCREASE AGAIN ON SATURDAY...AS
AN UPPER LEVEL DISTURBANCE MOVES ACROSS THE REGION.
MINIMUM RELATIVE HUMIDITY VALUES THIS AFTERNOON ARE EXPECTED TO BE
BETWEEN 50 AND 60 PERCENT...INCREASING TO MAXIMUM VALUES OF 90 TO
100 PERCENT TONIGHT. MIN RH VALUES FRIDAY WILL DROP TO AROUND 35 TO
50 PERCENT DURING THE AFTERNOON.
WINDS TODAY WILL BE SOUTH-SOUTHWEST AROUND 5 TO 10 MPH...BECOMING
SOUTHWEST AROUND 5 MPH TONIGHT. WINDS ON FRIDAY WILL BE WESTERLY AT
5 TO 15 MPH.
&&
.HYDROLOGY...
NO MAIN STEM RIVER FLOODING IS FORECAST THROUGH THE NEXT 5 DAYS.
FAIRLY WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY AS A
COLD FRONT CROSS THE AREA. WITH PWAT VALUES POTENTIALLY NEAR TWO
INCHES...THUNDERSTORMS WILL BE CAPABLE OF PRODUCING VERY HEAVY
RAINFALL...WHICH MAY CAUSE LOCALIZED MINOR FLOODING OF URBAN...LOW
LYING AND POOR DRAINAGE AREAS. ISOLATED FLASH FLOODING CANNOT BE
RULED OUT...BUT THE THREAT WILL NOT BE WIDESPREAD.
MAINLY DRY WEATHER WILL RETURN FOR TONIGHT THROUGH FRIDAY NIGHT.
SOME ADDITIONAL SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE
MAINLY DURING THE FIRST HALF OF THE WEEKEND.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...FRUGIS
NEAR TERM...FRUGIS/KL/JPV
SHORT TERM...JPV
LONG TERM...GJM
AVIATION...KL/GJM
FIRE WEATHER...JPV
HYDROLOGY...FRUGIS/JPV
AREA FORECAST DISCUSSION
NWS NEW YORK NY
221 AM EDT THU JUL 30 2015
.SYNOPSIS...
WEAK HIGH PRESSURE WILL SLIDE OFF THE MID ATLANTIC COAST TONIGHT.
A COLD FRONT WILL APPROACH ON THURSDAY...AND MOVE ACROSS THURSDAY
NIGHT. WEAK HIGH PRESSURE WILL RETURN FRIDAY THROUGH SATURDAY. A
WEAK LOW PRESSURE TROUGH WILL MOVE THROUGH SATURDAY NIGHT INTO
EARLY SUNDAY...FOLLOWED BY ANOTHER WEAK TROUGH SUNDAY NIGHT. A
COLD FRONT WILL APPROACH MONDAY NIGHT...AND REMAIN NEARBY THROUGH
MID WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
FORECAST OVERNIGHT REMAINS ON TRACK. UPDATED THE NEAR TERM GRIDS
TO BETTER REFLECT TRENDS IN LATEST OBSERVATIONS AND MODEL DATA
MAINLY WITH RESPECT TO TEMPERATURES AND DEWPOINTS. ADDED IN SOME
PATCHY FOG TOWARDS DAYBREAK ACROSS EASTERN SECTIONS WHERE LOWER
TEMP AND DEWPOINT DEPRESSIONS RESIDE.
A LARGE CONSENSUS OF BOTH SYNOPTIC AND MESOSCALE MODELS POINTING
TOWARDS SOME CONVECTIVE DEVELOPMENT NEAR AND WEST OF NYC AFTER
08Z. POPS WERE LEFT AS PREVIOUSLY FORECAST.
WARM AND MUGGY TONIGHT WITH LOWS IN THE 70S FOR MUCH OF THE
AREA ALTHOUGH A FEW SPOTS IN THE NYC METRO MAY STRUGGLE TO FALL
BELOW 80 DEGREES.
CONVECTION IN PARTS OF THE MID ATLANTIC AND CENTRAL
APPALACHIANS ASSOCIATED WITH AN APPROACHING SHORTWAVE HAS
LARGELY DISSIPATED OVER THE LAST FEW HOURS. NOT EXPECTING MUCH IN
THE WAY OF CONVECTIVE ACTIVITY WITH THIS SHORTWAVE...BUT AN ISO
SHOWER OR STORM CANNOT BE RULED OUT BEFORE DAYBREAK. THE LAST
SEVERAL RUNS OF THE HRRR HINT AT THIS POSSIBILITY.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/...
COULD STILL SEE ISO TO WDLY SCT ELEVATED CONVECTION FROM NYC
METRO NORTH/WEST IN THE MORNING AS THE LEADING SHORTWAVE MOVES
THROUGH. APPROACHING COLD FRONT SHOULD BRING SCT TO NUMEROUS TSTMS
FROM LATE AFTERNOON INTO THE EVENING AS AIR MASS
DESTABILIZES...WITH SBCAPE UP TO 1000 J/KG. THERE SHOULD BE ENOUGH
SHEAR TO SUPPORT AN ORGANIZED LINE OF STORMS OR MULTI-CELL
CLUSTERS...AND GIVEN A SW LLJ UP TO 35 KT AS FCST PER NAM...THESE
STORMS HAVE A BETTER CHANCE OF SURVIVING AS THEY MOVE PAST NYC
METRO AND THE LOWER HUDSON VALLEY INTO LONG ISLAND AND CT.
STRONGER CELLS HAVE POTENTIAL TO PRODUCE STRONG WIND GUSTS AND
DUMP LOCALLY HEAVY RAINFALL AS PW INCREASES TO JUST OVER 2 INCHES.
HIGHS ON THURSDAY SHOULD BE NOT QUITE AS WARM AS TODAY...GENERALLY
85-90...BUT WITH HIGHER DEWPOINTS MAX HEAT INDEX VALUES SHOULD
STILL BE SIMILAR TO THOSE OF TODAY...STILL REACHING THE MID 90S
EXCEPT IN THE HIGHER ELEVATIONS AND EASTERN COASTAL SECTIONS...SO
THE HEAT ADVY WILL CONTINUE FOR NYC.
THERE IS A HIGH RISK OF RIP CURRENTS AT OCEAN BEACHES ON
THURSDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
LONG WAVE UPPER LEVEL TROUGH WILL BE OVER THE NORTHEAST U.S. FOR
MUCH OF THIS TIME PERIOD. AT THE SURFACE...A COLD FRONT WILL REMAIN
JUST OFF THE EAST COAST FRIDAY...WITH WEAK HIGH PRESSURE BUILDING
IN. SUBSIDENCE FROM THIS HIGH SHOULD KEEP THE AREA DRY THROUGH MUCH
OF SATURDAY. A WEAK SURFACE TROUGH APPROACHES LATE
SATURDAY...WEAKENING AS IT DOES SO. 12Z GFS DOES SEEM MORE POTENT AS
OPPOSED TO THE 00Z ECMWF AND BRINGS THE TROUGH THROUGH LATE SATURDAY
NIGHT WITH A BRIEF PERIOD OF SHOWERS AND THUNDERSTORMS. SOME
INSTABILITY PRECEDING THE TROUGH...SO THUNDERSTORMS ARE POSSIBLE.
HOWEVER...JET DYNAMICS LOOK WEAK...THOUGH LIFT WITH THE TROUGH AT
LEAST EARLY IN THE NIGHT LOOKS DECENT ACCORDING TO THE 12Z GFS.
HOWEVER...LIFT QUICKLY WEAKENS AS THE TROUGH MOVES EAST LATE
SATURDAY NIGHT.
WEAK HIGH PRESSURE BUILDS IN FOR SUNDAY AND MONDAY WITH A COLD FRONT
APPROACHING MONDAY NIGHT. COLD FRONT SLOWS ITS APPROACH AND BECOMES
NEARLY STATIONARY IN THE VICINITY MONDAY NIGHT INTO WEDNESDAY.
AGAIN...SOME INSTABILITY OVER THE AREA AS THE FRONT MOVES
THROUGH...MAINLY FOR EASTERN SECTIONS...SO THUNDERSTORMS ARE ONCE
AGAIN POSSIBLE. LIFTED INDICES -8 TO -2 DURING TUESDAY NIGHT...WITH
LIFT BEING PROVIDED BY THE FRONT. MOISTURE IS ALSO AVAILABLE...WITH
SURFACE DEWPOINTS IN THE 60S AND PW RANGING FROM 1.25-1.50...THOUGH
THEY ARE NOT EXCEPTIONALLY HIGH.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
A SOUTHERLY FLOW CONTINUES AROUND HIGH PRESSURE OFF THE MID
ATLANTIC COAST AS A COLD FRONT THROUGH THE GREAT LAKES AND INTO
OHIO SLOWLY APPROACHES.
GENERALLY VFR THROUGH THE MORNING...ALTHOUGH ISOLD MVFR IN
FOG/HAZE DEVELOPING. SEVERAL PIECES OF GUIDANCE INDICATING WDLY
SCT SHOWER ACTIVITY DEVELOPING OVER CENTRAL/NRN NJ BETWEEN 09Z AND
12Z AND TRACKING TO THE NE THROUGH 15Z OR SO. HAVE INCLUDED VCSH
AT MOST TERMINALS TO ACCOUNT FOR THIS...BUT WOULD LIKE TO SEE
SOMETHING ON RADAR BEFORE ADDING IT INTO PREVAILING OR TEMPO.
THE COLD FRONT AND A WEAK PRE-FRONTAL TROUGH WILL BE MOVING INTO
THE TERMINALS AROUND 18Z TODAY AND MOVE THROUGH THIS EVENING.
SCATTERED SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE FRONT WITH
MVFR CONDITIONS...OR POSSIBLY IFR IN STRONGER STORMS. THERE IS A
HIGHER CHANCE OF CONVECTION FROM THE NYC TERMINALS AND AREAS WEST.
WILL CONTINUE TO INDICATE THE CHANCES WITH A PROB GROUP.
HEAVY RAIN WILL LIKELY ACCOMPANY ANY SHOWERS THIS MORNING AND
ESPECIALLY IN TSTMS THIS AFTN/EVE. THIS WILL DROP VSBYS TO IFR OR
LOWER IN THE HEAVIEST ACTIVITY.
MODERATE TO HIGH CONFIDENCE IN WIND FORECAST...GUSTS IN THE UPPER
TEENS TO LOWER 20S POSSIBLE AT KJFK AS WELL AS OTHER COASTAL
TERMINALS.
.OUTLOOK FOR 06Z FRIDAY THROUGH MONDAY...
.THURSDAY NIGHT...MVFR CONDS IN FOG/HZ BECOMING VFR.
.FRIDAY-MONDAY...VFR.
&&
.MARINE...
QUIET THROUGH THU MORNING. THEN AS SW FLOW INCREASES TO 15-20 KT
WITH FAVORABLE FETCH...OCEAN SEAS SHOULD BUILD TO 5-6 FT THU
AFTERNOON AND NIGHT. LOW LEVEL JET PASSING OHD SHOULD MIX TO THE
SFC...WITH GUSTS UP TO 25 KT LIKELY ON THE OCEAN AND THE BAYS OF
LONG ISLAND. SCA ISSUED FOR THESE HAZARDS. TSTMS WILL ALSO BE A
HAZARD WITH A COLD FRONTAL PASSAGE THU AFTERNOON/EVENING.
OCEAN SEAS COULD BUILD TO AROUND 5 FT SAT NIGHT INTO SUNDAY...
AND AGAIN LATE SUNDAY INTO MONDAY MORNING. THEN A MORE PROLONGED
PERIOD OF 5-FT OCEAN SEAS IS POSSIBLE FROM MON NIGHT INTO MID
WEEK.
&&
.HYDROLOGY...
BASIN AVG QPF OF 1/2 TO 3/4 INCH POSSIBLE IN THE LOWER HUDSON
VALLEY AND NE NJ...WITH UP TO 1/2 INCH ELSEWHERE. WITH PW OVER 2
INCHES THU AFTERNOON AND EVENING...LOCALLY HEAVY RAINFALL IS
POSSIBLE WITH ANY STRONGER CONVECTION. MINOR URBAN/POOR DRAINAGE
FLOODING IS THE MOST LIKELY OUTCOME.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NYZ072>075-176-
178.
HIGH RIP CURRENT RISK FROM 6 AM EDT THIS MORNING THROUGH THIS
EVENING FOR NYZ075-080-081-178-179.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT THIS
EVENING FOR ANZ340-345.
SMALL CRAFT ADVISORY FROM NOON TODAY TO MIDNIGHT EDT TONIGHT
FOR ANZ355.
SMALL CRAFT ADVISORY FROM NOON TODAY TO 6 AM EDT FRIDAY FOR
ANZ350-353.
&&
$$
SYNOPSIS...GOODMAN/JP
NEAR TERM...GOODMAN/JM/DS
SHORT TERM...GOODMAN/DS
LONG TERM...JP
AVIATION...24
MARINE...GOODMAN/JP
HYDROLOGY...GOODMAN/JP
AREA FORECAST DISCUSSION
NWS NEW YORK NY
119 AM EDT THU JUL 30 2015
.SYNOPSIS...
WEAK HIGH PRESSURE WILL SLIDE OFF THE MID ATLANTIC COAST TONIGHT.
A COLD FRONT WILL APPROACH ON THURSDAY...AND MOVE ACROSS THURSDAY
NIGHT. WEAK HIGH PRESSURE WILL RETURN FRIDAY THROUGH SATURDAY. A
WEAK LOW PRESSURE TROUGH WILL MOVE THROUGH SATURDAY NIGHT INTO
EARLY SUNDAY...FOLLOWED BY ANOTHER WEAK TROUGH SUNDAY NIGHT. A
COLD FRONT WILL APPROACH MONDAY NIGHT...AND REMAIN NEARBY THROUGH
MID WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
FORECAST OVERNIGHT REMAINS ON TRACK. UPDATED THE NEAR TERM GRIDS
TO BETTER REFLECT TRENDS IN LATEST OBSERVATIONS AND MODEL DATA
MAINLY WITH RESPECT TO TEMPERATURES AND DEWPOINTS. ADDED IN SOME
PATCHY FOG TOWARDS DAYBREAK ACROSS EASTERN SECTIONS WHERE LOWER
TEMP AND DEWPOINT DEPRESSIONS RESIDE.
A LARGE CONSENSUS OF BOTH SYNOPTIC AND MESOSCALE MODELS POINTING
TOWARDS SOME CONVECTIVE DEVELOPMENT NEAR AND WEST OF NYC AFTER
08Z. POPS WERE LEFT AS PREVIOUSLY FORECAST.
WARM AND MUGGY TONIGHT WITH LOWS IN THE 70S FOR MUCH OF THE
AREA ALTHOUGH A FEW SPOTS IN THE NYC METRO MAY STRUGGLE TO FALL
BELOW 80 DEGREES.
CONVECTION IN PARTS OF THE MID ATLANTIC AND CENTRAL
APPALACHIANS ASSOCIATED WITH AN APPROACHING SHORTWAVE HAS
LARGELY DISSIPATED OVER THE LAST FEW HOURS. NOT EXPECTING MUCH IN
THE WAY OF CONVECTIVE ACTIVITY WITH THIS SHORTWAVE...BUT AN ISO
SHOWER OR STORM CANNOT BE RULED OUT BEFORE DAYBREAK. THE LAST
SEVERAL RUNS OF THE HRRR HINT AT THIS POSSIBILITY.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/...
COULD STILL SEE ISO TO WDLY SCT ELEVATED CONVECTION FROM NYC
METRO NORTH/WEST IN THE MORNING AS THE LEADING SHORTWAVE MOVES
THROUGH. APPROACHING COLD FRONT SHOULD BRING SCT TO NUMEROUS TSTMS
FROM LATE AFTERNOON INTO THE EVENING AS AIR MASS
DESTABILIZES...WITH SBCAPE UP TO 1000 J/KG. THERE SHOULD BE ENOUGH
SHEAR TO SUPPORT AN ORGANIZED LINE OF STORMS OR MULTI-CELL
CLUSTERS...AND GIVEN A SW LLJ UP TO 35 KT AS FCST PER NAM...THESE
STORMS HAVE A BETTER CHANCE OF SURVIVING AS THEY MOVE PAST NYC
METRO AND THE LOWER HUDSON VALLEY INTO LONG ISLAND AND CT.
STRONGER CELLS HAVE POTENTIAL TO PRODUCE STRONG WIND GUSTS AND
DUMP LOCALLY HEAVY RAINFALL AS PW INCREASES TO JUST OVER 2 INCHES.
HIGHS ON THURSDAY SHOULD BE NOT QUITE AS WARM AS TODAY...GENERALLY
85-90...BUT WITH HIGHER DEWPOINTS MAX HEAT INDEX VALUES SHOULD
STILL BE SIMILAR TO THOSE OF TODAY...STILL REACHING THE MID 90S
EXCEPT IN THE HIGHER ELEVATIONS AND EASTERN COASTAL SECTIONS...SO
THE HEAT ADVY WILL CONTINUE FOR NYC.
THERE IS A HIGH RISK OF RIP CURRENTS AT OCEAN BEACHES ON
THURSDAY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
LONG WAVE UPPER LEVEL TROUGH WILL BE OVER THE NORTHEAST U.S. FOR
MUCH OF THIS TIME PERIOD. AT THE SURFACE...A COLD FRONT WILL REMAIN
JUST OFF THE EAST COAST FRIDAY...WITH WEAK HIGH PRESSURE BUILDING
IN. SUBSIDENCE FROM THIS HIGH SHOULD KEEP THE AREA DRY THROUGH MUCH
OF SATURDAY. A WEAK SURFACE TROUGH APPROACHES LATE
SATURDAY...WEAKENING AS IT DOES SO. 12Z GFS DOES SEEM MORE POTENT AS
OPPOSED TO THE 00Z ECMWF AND BRINGS THE TROUGH THROUGH LATE SATURDAY
NIGHT WITH A BRIEF PERIOD OF SHOWERS AND THUNDERSTORMS. SOME
INSTABILITY PRECEDING THE TROUGH...SO THUNDERSTORMS ARE POSSIBLE.
HOWEVER...JET DYNAMICS LOOK WEAK...THOUGH LIFT WITH THE TROUGH AT
LEAST EARLY IN THE NIGHT LOOKS DECENT ACCORDING TO THE 12Z GFS.
HOWEVER...LIFT QUICKLY WEAKENS AS THE TROUGH MOVES EAST LATE
SATURDAY NIGHT.
WEAK HIGH PRESSURE BUILDS IN FOR SUNDAY AND MONDAY WITH A COLD FRONT
APPROACHING MONDAY NIGHT. COLD FRONT SLOWS ITS APPROACH AND BECOMES
NEARLY STATIONARY IN THE VICINITY MONDAY NIGHT INTO WEDNESDAY.
AGAIN...SOME INSTABILITY OVER THE AREA AS THE FRONT MOVES
THROUGH...MAINLY FOR EASTERN SECTIONS...SO THUNDERSTORMS ARE ONCE
AGAIN POSSIBLE. LIFTED INDICES -8 TO -2 DURING TUESDAY NIGHT...WITH
LIFT BEING PROVIDED BY THE FRONT. MOISTURE IS ALSO AVAILABLE...WITH
SURFACE DEWPOINTS IN THE 60S AND PW RANGING FROM 1.25-1.50...THOUGH
THEY ARE NOT EXCEPTIONALLY HIGH.
&&
.AVIATION /05Z THURSDAY THROUGH MONDAY/...
A SOUTHERLY FLOW CONTINUES AROUND HIGH PRESSURE OFF THE MID
ATLANTIC COAST AS A COLD FRONT THROUGH THE GREAT LAKES AND INTO
OHIO SLOWLY APPROACHES. THE COLD FRONT AND A WEAK PRE FRONTAL TROUGH
WILL BE MOVING INTO THE TERMINALS AROUND 18Z THURSDAY AND MOVE
THROUGH THURSDAY EVENING. SCATTERED SHOWERS AND THUNDERSTORMS WILL
ACCOMPANY THE FRONT WITH MVFR CONDITIONS...OR POSSIBLY IFR IN
STRONGER STORMS. THERE IS A HIGHER CHANCE OF CONVECTION FROM THE NYC
TERMINALS AND AREAS WEST. WILL CONTINUE TO INDICATE THE CHANCES WITH
A PROB GROUP.
OTHERWISE VFR UNTIL TOWARD MORNING WHEN MVFR VISIBILITIES WILL BE
POSSIBLE IN FOG AND/OR HAZE.
.OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY...
.THURSDAY NIGHT...SCATTERED SHOWERS AND THUNDERSTORMS ENDING IN THE
EVENING WITH MVFR CONDITIONS POSSIBLE...THEN BECOMING VFR.
.FRIDAY-MONDAY...VFR.
&&
.MARINE...
QUIET THROUGH THU MORNING. THEN AS SW FLOW INCREASES TO 15-20 KT
WITH FAVORABLE FETCH...OCEAN SEAS SHOULD BUILD TO 5-6 FT THU
AFTERNOON AND NIGHT. LOW LEVEL JET PASSING OHD SHOULD MIX TO THE
SFC...WITH GUSTS UP TO 25 KT LIKELY ON THE OCEAN AND THE BAYS OF
LONG ISLAND. SCA ISSUED FOR THESE HAZARDS. TSTMS WILL ALSO BE A
HAZARD WITH A COLD FRONTAL PASSAGE THU AFTERNOON/EVENING.
OCEAN SEAS COULD BUILD TO AROUND 5 FT SAT NIGHT INTO SUNDAY...
AND AGAIN LATE SUNDAY INTO MONDAY MORNING. THEN A MORE PROLONGED
PERIOD OF 5-FT OCEAN SEAS IS POSSIBLE FROM MON NIGHT INTO MID
WEEK.
&&
.HYDROLOGY...
BASIN AVG QPF OF 1/2 TO 3/4 INCH POSSIBLE IN THE LOWER HUDSON
VALLEY AND NE NJ...WITH UP TO 1/2 INCH ELSEWHERE. WITH PW OVER 2
INCHES THU AFTERNOON AND EVENING...LOCALLY HEAVY RAINFALL IS
POSSIBLE WITH ANY STRONGER CONVECTION. MINOR URBAN/POOR DRAINAGE
FLOODING IS THE MOST LIKELY OUTCOME.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NYZ072>075-176-
178.
HIGH RIP CURRENT RISK FROM 6 AM EDT THIS MORNING THROUGH THIS
EVENING FOR NYZ075-080-081-178-179.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT THIS
EVENING FOR ANZ340-345.
SMALL CRAFT ADVISORY FROM NOON TODAY TO MIDNIGHT EDT TONIGHT
FOR ANZ355.
SMALL CRAFT ADVISORY FROM NOON TODAY TO 6 AM EDT FRIDAY FOR
ANZ350-353.
&&
$$
SYNOPSIS...GOODMAN/JP
NEAR TERM...GOODMAN/JM/DS
SHORT TERM...GOODMAN/DS
LONG TERM...JP
AVIATION...MET
MARINE...GOODMAN/JP
HYDROLOGY...GOODMAN/JP
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1139 AM EDT THU JUL 30 2015
.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE THROUGH OUR REGION TONIGHT, THEN
STALLS TO OUR SOUTH AND EAST. THE NEXT WEAK COLD FRONT SHOULD
CROSS OUR AREA LATE SATURDAY BEFORE STALLING OFFSHORE SUNDAY. A
FEW WEAK WAVES OF LOW PRESSURE MAY TRACK ALONG THE FRONT AND
POSSIBLY MOVE CLOSER TO OUR COAST MONDAY AS HIGH PRESSURE TRIES TO
ARRIVE. A STRONGER COLD FRONT IS THEN FORECAST TO ARRIVE DURING
TUESDAY, BEFORE ALSO STALLING NEARBY ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE APPROACHING COLD FRONT EXTENDED FROM THE FINGER LAKES ACROSS
CENTRAL PENNSYLVANIA DOWN INTO WEST VIRGINIA LATE THIS MORNING. A
LINE OF SHOWERS AND ISOLATED THUNDERSTORMS WAS OUT AHEAD OF THE
FRONT AND IT WAS APPROACHING SCRANTON, HARRISBURG AND THE WESTERN
SUBURBS OF WASHINGTON. AS THE PRECIPITATION MOVES EASTWARD INTO
INCREASINGLY UNSTABLE AIR, THE THUNDERSTORMS SHOULD BECOME MORE
NUMEROUS AND THEY WILL LIKELY STRENGTHEN. MUCH OF OUR FORECAST
AREA REMAINS UNDER A MARGINAL RISK FOR SEVERE WEATHER FOR THIS
AFTERNOON INTO THIS EVENING.
THE HRRR SEEMS TO HAVE A GOOD HANDLE ON THE TIMING OF THE
CONVECTIVE LINE. IT SHOULD BE INTO THE ALLENTOWN AND READING AREAS
BY 200 PM AND IT IS EXPECTED TO REACH THE INTERSTATE 95 CORRIDOR
IN OUR REGION AROUND OR SHORTLY AFTER 400 PM. THE SHOWERS AND
THUNDERSTORMS ARE ANTICIPATED TO BE NEARING THE COAST AT 600 PM.
MAXIMUM TEMPERATURES ARE FORECAST TO BE NEAR 90 DEGREES IN MUCH
OF OUR AREA. READINGS SHOULD NOT GET OUT OF THE 80S IN THE
ELEVATED TERRAIN UP NORTH AND ALONG THE IMMEDIATE COAST. DEW
POINT READINGS ARE EXPECTED TO BE MOSTLY IN THE LOWER 70S. WE WILL
CONTINUE THE EXCESSIVE HEAT WARNING FOR THE HIGHLY URBANIZED AREAS
ALONG THE INTERSTATE 95 CORRIDOR.
THE WIND SHOULD REMAIN FROM THE SOUTHWEST AROUND 6 TO 12 MPH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
THE AFOREMENTIONED COLD FRONT WILL CONTINUE ITS TREK TOWARD THE
COAST AND SHOULD MOVE OFFSHORE TONIGHT. THE SHOWERS AND
THUNDERSTORMS WILL CONTINUE INTO TONIGHT AND WILL END FROM
NORTHWEST TO SOUTHEAST AS THE FRONT PUSHES OFF THE COAST AND THEN
FURTHER OFFSHORE. AS THE FRONT PUSHES AWAY, WE WILL ALSO SEE SOME
CLEARING BEHIND IT AND AREAS TO THE NORTH AND WEST OF PHILLY WILL
BE ABLE TO COOL OFF A BIT AND DROP DOWN INTO THE LOWER TO MID 60S
OVERNIGHT. AREAS TO THE SOUTH AND EAST OF PHILLY WILL HOLD ONTO
THE CLOUD COVER A BIT LONGER AND WILL LIKELY REMAIN IN THE UPPER
60S TO LOWER 70S FOR OVERNIGHT LOWS. EVEN WITH THE CLEARING, LOW
LEVEL MOISTURE MAY HANG AROUND FOR A BIT AND PATCHY FOG WILL
REMAIN POSSIBLE.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
THE SYNOPTIC SETUP IS COMPRISED OF AN UPPER-LEVEL TROUGH FROM THE
GREAT LAKES TO THE NORTHEAST FRIDAY WITH SOME AMPLIFICATION INTO
THE WEEKEND. DESPITE A WARM TO HOT AIRMASS IN PLACE, A SUBSTANTIAL
REDUCTION IN THE DEW POINTS IS EXPECTED FRIDAY AND EVEN FOR THE
WEEKEND OVERALL FOR THE CWA. A WEAK FRONT MOVES THROUGH LATE
SATURDAY WITH SOME POTENTIALLY TRICKY CONVECTIVE CHCS, THEN THE
NEXT ONE ARRIVES DURING TUESDAY BEFORE STALLING NEARBY WEDNESDAY.
THERE IS MORE UNCERTAINTY IN THE DETAILS ESPECIALLY NEXT WEEK AS
THE AMPLITUDE OF THE TROUGH AND THE POSITIONING OF FRONTAL
BOUNDARIES WILL IMPACT OUR SENSIBLE WEATHER. WE USED A MODEL BLEND
FRIDAY THROUGH SUNDAY, THEN WENT WITH MOSTLY A WPC/CONTINUITY
BLEND THEREAFTER.
FOR FRIDAY...AN INITIAL FRONT IS STALLED OFFSHORE AS IT BECOMES
TRAPPED BETWEEN A RIDGE IN THE WESTERN ATLANTIC AND A TROUGH FROM
THE GREAT LAKES TO THE NORTHEAST. ANY REMAINING FRONTAL FORCING AND
ASSOCIATED CONVECTION SHOULD REMAIN WELL OFFSHORE, MEANWHILE A
NOTICEABLE DRIER AIRMASS SETTLES INTO OUR AREA. DESPITE IT STILL
BEING WARM TO HOT ACROSS THE CWA, THE LOWER DEW POINTS WILL RESULT
IN A MUCH LESS HUMID FEEL /EVEN COOLER AT NIGHT/. THE AFOREMENTIONED
UPPER-LEVEL TROUGH AMPLIFIES SOME ESPECIALLY TO OUR NORTHWEST
THROUGH NORTHEAST, AND SOME UPSTREAM CONVECTION MAY TRY TO MAKE A
RUN AT OUR NORTHWEST ZONES VERY LATE AT NIGHT. OVERALL, THIS LOOKS
LIKE A VERY SMALL CHC PLUS WITH THE INITIAL DRIER AIRMASS IN PLACE
AND THEREFORE WE OPTED TO LEAVE THE NIGHT TIME FRAME DRY.
FOR SATURDAY AND SUNDAY...AN UPPER-LEVEL TROUGH REMAINS ACROSS THE
NORTHEAST ALTHOUGH IT MAY WEAKEN SOME SUNDAY AS A RIDGE IN THE
WESTERN ATLANTIC TRIES TO EXPAND NORTHWESTWARD. THIS KEEPS A STALLED
FRONTAL BOUNDARY OFFSHORE HOWEVER IT APPEARS THAT WEAK RIPPLES OF
ENERGY ALONG IT REMAINS TO OUR EAST. A SECONDARY FRONTAL ZONE IS
FORECAST TO MOVE THROUGH LATE SATURDAY INTO SUNDAY, AND THE GREATEST
LIFT AND SHEAR IS MOSTLY FROM NEAR OUR NORTHERN ZONES ON NORTHWARD
INTO NEW ENGLAND. THE DEW POINTS SHOULD START TO INCH BACK UPWARD
AGAIN LATER SATURDAY, HOWEVER ENOUGH DRYING MAY LIMIT MUCH
CONVECTIVE DEVELOPMENT. SOME GUIDANCE DOES INITIATE MORE CONVECTION
BY LATE SATURDAY FROM NORTHEASTERN PENNSYLVANIA TO NORTHERN NEW
JERSEY THEN SLIDES IT SOUTHEASTWARD. THERE MAY BE ENOUGH SHEAR WITH
INCREASING INSTABILITY TO ALLOW FOR A GUSTY THUNDERSTORM, HOWEVER
THIS IS DEPENDENT ON THE AIRMASS MOISTENING UP SUFFICIENTLY AS THE
UPPER-LEVEL TROUGH REMAINS IN PLACE. FOR NOW, WE CONTINUED SOME LOW
END CHC POPS ACROSS THE FAR NORTH SATURDAY AFTERNOON.
THE FRONT LOOKS TO STALL JUST OFFSHORE GIVEN WEAKER FLOW WITH A
SOUTHEASTERN EXTENT, HOWEVER SOME WEAK IMPULSES MAY TRACK ALONG IT.
IT APPEARS THAT ANY CONVECTION LEFTOVER WITH THE FRONT IS OFFSHORE,
THEREFORE WE HAVE A DRY SUNDAY. IT WILL CONTINUE TO BE WARM GIVEN A
SIMILAR PATTERN AND THE DEW POINTS WILL PROBABLY INCREASE A BIT
MAINLY SUNDAY NIGHT ACROSS THE SOUTHERN AND EASTERN AREAS.
FOR MONDAY AND TUESDAY...AS THE UPPER-LEVEL TROUGH RELOADS FROM THE
WEST, IT MAY SUPPORT WEAK IMPULSES TRAVERSING THE OFFSHORE FRONT. IF
THIS OCCURS AND WITH THE UPPER-LEVEL FLOW TURNING MORE SOUTHWESTERLY
FOR A TIME, THE FRONT MAY INCH BACK INTO OUR AREA TO HELP FOCUS SOME
CONVECTION MONDAY. THIS LOOKS WEAK OVERALL WITH THE MAIN FORCING
REMAINING MOSTLY ACROSS THE GREAT LAKES REGION MONDAY. TIED TO THIS
FORCING, ANOTHER COLD FRONT ARRIVES DURING TUESDAY WITH THE
POTENTIAL FOR SOME CONVECTION ALTHOUGH THE STRONGER SHEAR MAY AGAIN
SLIDE TO OUR NORTH. WE OPTED TO GO CLOSE TO THE 00Z WPC GUIDANCE
WHICH CARRIES POPS OF LOW END CHC OR LESS.
FOR WEDNESDAY...AS THE UPPER-LEVEL TROUGH STARTS TO WEAKEN IN THE
NORTHEAST, THE FRONTAL BOUNDARY FROM TUESDAY SHOULD SLOW OR EVEN
STALL IN OUR VICINITY. THIS COULD HELP FOCUS SOME CONVECTIVE
DEVELOPMENT ESPECIALLY DURING PEAK HEATING, WITH POSSIBLE
CONVECTIVELY INDUCED IMPULSES ARRIVING FROM THE WEST. THERE IS MUCH
MORE UNCERTAINTY THIS FAR OUT AS THE POSITIONING OF THE UPPER-LEVEL
TROUGH WILL GOVERN THE FRONTAL ZONE PLACEMENT AND SUBSEQUENT
CONVECTIVE CHCS.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
SOME MVFR CEILINGS WERE LINGERING IN OUR REGION AROUND 1530Z. THE
CLOUDS WILL CONTINUE TO LIFT.
SHOWERS AND THUNDERSTORMS, ASSOCIATED WITH AN APPROACHING COLD
FRONT, ARE EXPECTED TO REACH KRDG AND KABE BETWEEN 17-18Z. THE
SHOWERS AND THUNDERSTORMS ARE FORECAST TO REACH KILG, KPHL, KPNE
AND KTTN AROUND 20Z. THEY SHOULD PUSH THROUGH KMIV AND KACY
BETWEEN 22-00Z. CLEARING IS EXPECTED TO OCCUR TONIGHT.
SOUTH TO SOUTHWEST WINDS AROUND 5 TO 10 ARE EXPECTED THROUGH TODAY,
BECOMING NORTHWEST BEHIND THE FRONTAL PASSAGE.
OUTLOOK...
FRIDAY...A CHANCE OF SOME FOG EARLY MAINLY AT KMIV AND KACY,
OTHERWISE VFR. NORTHWEST WINDS AROUND 10 KNOTS, THEN DIMINISHING TO
NEAR 5 KNOTS AT NIGHT AND BECOMING SOUTHWESTERLY.
SATURDAY...VFR OVERALL. A SHOWER OR THUNDERSTORM POSSIBLE IN THE
AFTERNOON AND EVENING MAINLY NORTH AND WEST OF KPHL. SOUTHWEST WINDS
5-10 KNOTS.
SUNDAY AND MONDAY...VFR IS ANTICIPATED.
&&
.MARINE...
A SOUTH TO SOUTHWEST FLOW OF AROUND 10 TO 15 KNOTS WITH GUSTS UP TO
20 KNOTS IS EXPECTED ON THE AREA WATERS THROUGH TONIGHT. SEAS WILL
REMAIN AROUND 2 TO 4 FEET.
A COLD FRONT WILL APPROACH FROM THE WEST AND REACH THE AREA
WATERS LATE TONIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
PRECEDE THE FRONTAL PASSAGE.
OUTLOOK...
FRIDAY THROUGH MONDAY...THE CONDITIONS ARE ANTICIPATED TO BE BELOW
SMALL CRAFT ADVISORY CRITERIA OVERALL. A LINGERING FRONT OFFSHORE
FRIDAY INTO SATURDAY, THEN ANOTHER FRONT MOVES THROUGH LATE SATURDAY
AND POSSIBLY STALLS NEARBY INTO MONDAY.
&&
.RIP CURRENTS...
A MODERATE RISK OF DANGEROUS RIP CURRENTS IS FORECAST FOR
TODAY, WITH INCREASING SOUTH TO SOUTHWEST FLOW AHEAD OF A COLD
FRONT AND THE FULL MOON ON FRIDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...EXCESSIVE HEAT WARNING UNTIL 6 PM EDT THIS EVENING FOR PAZ070-
071-102-104-106.
NJ...EXCESSIVE HEAT WARNING UNTIL 6 PM EDT THIS EVENING FOR NJZ015-
017>019.
DE...EXCESSIVE HEAT WARNING UNTIL 6 PM EDT THIS EVENING FOR DEZ001.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GORSE
NEAR TERM...IOVINO/YAROSH
SHORT TERM...MEOLA
LONG TERM...GORSE
AVIATION...GORSE/MEOLA
MARINE...GORSE/MEOLA
RIP CURRENTS...MEOLA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
952 AM EDT THU JUL 30 2015
.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE THROUGH OUR REGION TONIGHT, THEN
STALLS TO OUR SOUTH AND EAST. THE NEXT WEAK COLD FRONT SHOULD
CROSS OUR AREA LATE SATURDAY BEFORE STALLING OFFSHORE SUNDAY. A
FEW WEAK WAVES OF LOW PRESSURE MAY TRACK ALONG THE FRONT AND
POSSIBLY MOVE CLOSER TO OUR COAST MONDAY AS HIGH PRESSURE TRIES TO
ARRIVE. A STRONGER COLD FRONT IS THEN FORECAST TO ARRIVE DURING
TUESDAY, BEFORE ALSO STALLING NEARBY ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
ISOLATED SHOWERS WERE LINGERING IN PARTS OF CENTRAL AND SOUTHERN
NEW JERSEY AROUND 930 AM. THE LIGHT PRECIPITATION WILL CONTINUE TO
LIFT NORTHEASTWARD AND WEAKEN DURING THE BALANCE OF THE MORNING.
THE APPROACHING COLD FRONT EXTENDED ACROSS WESTERN NEW YORK AND
WESTERN PENNSYLVANIA DOWN INTO WEST VIRGINIA AT MID MORNING. A
LINE OF SHOWERS AND ISOLATED THUNDERSTORMS WAS OUT AHEAD OF THE
FRONT AND IT EXTENDED THROUGH CENTRAL NEW YORK AND CENTRAL
PENNSYLVANIA. AS THE PRECIPITATION MOVES EASTWARD INTO
INCREASINGLY UNSTABLE AIR, THE THUNDERSTORMS SHOULD BECOME MORE
NUMEROUS AND THEY WILL LIKELY STRENGTHEN. MUCH OF OUR FORECAST
AREA REMAINS UNDER A MARGINAL RISK FOR SEVERE WEATHER FOR THIS
AFTERNOON INTO THIS EVENING.
THE HRRR SEEMS TO HAVE A GOOD HANDLE ON THE TIMING OF THE
CONVECTIVE LINE. IT SHOULD BE INTO THE ALLENTOWN AND READING AREAS
BY 200 PM AND IT IS EXPECTED TO REACH THE INTERSTATE 95 CORRIDOR
IN OUR REGION AROUND OR SHORTLY AFTER 400 PM. THE SHOWERS AND
THUNDERSTORMS ARE ANTICIPATED TO BE NEARING THE COAST AT 600 PM.
MAXIMUM TEMPERATURES ARE FORECAST TO BE NEAR 90 DEGREES IN MUCH
OF OUR AREA. READINGS SHOULD NOT GET OUT OF THE 80S IN THE
ELEVATED TERRAIN UP NORTH AND ALONG THE IMMEDIATE COAST. DEW
POINT READINGS ARE EXPECTED TO BE MOSTLY IN THE LOWER 70S. WE WILL
CONTINUE THE EXCESSIVE HEAT WARNING FOR THE HIGHLY URBANIZED AREAS
ALONG THE INTERSTATE 95 CORRIDOR.
THE WIND SHOULD REMAIN FROM THE SOUTHWEST AROUND 6 TO 12 MPH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
THE AFOREMENTIONED COLD FRONT WILL CONTINUE ITS TREK TOWARD THE
COAST AND SHOULD MOVE OFFSHORE TONIGHT. THE SHOWERS AND
THUNDERSTORMS WILL CONTINUE INTO TONIGHT AND WILL END FROM
NORTHWEST TO SOUTHEAST AS THE FRONT PUSHES OFF THE COAST AND THEN
FURTHER OFFSHORE. AS THE FRONT PUSHES AWAY, WE WILL ALSO SEE SOME
CLEARING BEHIND IT AND AREAS TO THE NORTH AND WEST OF PHILLY WILL
BE ABLE TO COOL OFF A BIT AND DROP DOWN INTO THE LOWER TO MID 60S
OVERNIGHT. AREAS TO THE SOUTH AND EAST OF PHILLY WILL HOLD ONTO
THE CLOUD COVER A BIT LONGER AND WILL LIKELY REMAIN IN THE UPPER
60S TO LOWER 70S FOR OVERNIGHT LOWS. EVEN WITH THE CLEARING, LOW
LEVEL MOISTURE MAY HANG AROUND FOR A BIT AND PATCHY FOG WILL
REMAIN POSSIBLE.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
THE SYNOPTIC SETUP IS COMPRISED OF AN UPPER-LEVEL TROUGH FROM THE
GREAT LAKES TO THE NORTHEAST FRIDAY WITH SOME AMPLIFICATION INTO
THE WEEKEND. DESPITE A WARM TO HOT AIRMASS IN PLACE, A SUBSTANTIAL
REDUCTION IN THE DEW POINTS IS EXPECTED FRIDAY AND EVEN FOR THE
WEEKEND OVERALL FOR THE CWA. A WEAK FRONT MOVES THROUGH LATE
SATURDAY WITH SOME POTENTIALLY TRICKY CONVECTIVE CHCS, THEN THE
NEXT ONE ARRIVES DURING TUESDAY BEFORE STALLING NEARBY WEDNESDAY.
THERE IS MORE UNCERTAINTY IN THE DETAILS ESPECIALLY NEXT WEEK AS
THE AMPLITUDE OF THE TROUGH AND THE POSITIONING OF FRONTAL
BOUNDARIES WILL IMPACT OUR SENSIBLE WEATHER. WE USED A MODEL BLEND
FRIDAY THROUGH SUNDAY, THEN WENT WITH MOSTLY A WPC/CONTINUITY
BLEND THEREAFTER.
FOR FRIDAY...AN INITIAL FRONT IS STALLED OFFSHORE AS IT BECOMES
TRAPPED BETWEEN A RIDGE IN THE WESTERN ATLANTIC AND A TROUGH FROM
THE GREAT LAKES TO THE NORTHEAST. ANY REMAINING FRONTAL FORCING AND
ASSOCIATED CONVECTION SHOULD REMAIN WELL OFFSHORE, MEANWHILE A
NOTICEABLE DRIER AIRMASS SETTLES INTO OUR AREA. DESPITE IT STILL
BEING WARM TO HOT ACROSS THE CWA, THE LOWER DEW POINTS WILL RESULT
IN A MUCH LESS HUMID FEEL /EVEN COOLER AT NIGHT/. THE AFOREMENTIONED
UPPER-LEVEL TROUGH AMPLIFIES SOME ESPECIALLY TO OUR NORTHWEST
THROUGH NORTHEAST, AND SOME UPSTREAM CONVECTION MAY TRY TO MAKE A
RUN AT OUR NORTHWEST ZONES VERY LATE AT NIGHT. OVERALL, THIS LOOKS
LIKE A VERY SMALL CHC PLUS WITH THE INITIAL DRIER AIRMASS IN PLACE
AND THEREFORE WE OPTED TO LEAVE THE NIGHT TIME FRAME DRY.
FOR SATURDAY AND SUNDAY...AN UPPER-LEVEL TROUGH REMAINS ACROSS THE
NORTHEAST ALTHOUGH IT MAY WEAKEN SOME SUNDAY AS A RIDGE IN THE
WESTERN ATLANTIC TRIES TO EXPAND NORTHWESTWARD. THIS KEEPS A STALLED
FRONTAL BOUNDARY OFFSHORE HOWEVER IT APPEARS THAT WEAK RIPPLES OF
ENERGY ALONG IT REMAINS TO OUR EAST. A SECONDARY FRONTAL ZONE IS
FORECAST TO MOVE THROUGH LATE SATURDAY INTO SUNDAY, AND THE GREATEST
LIFT AND SHEAR IS MOSTLY FROM NEAR OUR NORTHERN ZONES ON NORTHWARD
INTO NEW ENGLAND. THE DEW POINTS SHOULD START TO INCH BACK UPWARD
AGAIN LATER SATURDAY, HOWEVER ENOUGH DRYING MAY LIMIT MUCH
CONVECTIVE DEVELOPMENT. SOME GUIDANCE DOES INITIATE MORE CONVECTION
BY LATE SATURDAY FROM NORTHEASTERN PENNSYLVANIA TO NORTHERN NEW
JERSEY THEN SLIDES IT SOUTHEASTWARD. THERE MAY BE ENOUGH SHEAR WITH
INCREASING INSTABILITY TO ALLOW FOR A GUSTY THUNDERSTORM, HOWEVER
THIS IS DEPENDENT ON THE AIRMASS MOISTENING UP SUFFICIENTLY AS THE
UPPER-LEVEL TROUGH REMAINS IN PLACE. FOR NOW, WE CONTINUED SOME LOW
END CHC POPS ACROSS THE FAR NORTH SATURDAY AFTERNOON.
THE FRONT LOOKS TO STALL JUST OFFSHORE GIVEN WEAKER FLOW WITH A
SOUTHEASTERN EXTENT, HOWEVER SOME WEAK IMPULSES MAY TRACK ALONG IT.
IT APPEARS THAT ANY CONVECTION LEFTOVER WITH THE FRONT IS OFFSHORE,
THEREFORE WE HAVE A DRY SUNDAY. IT WILL CONTINUE TO BE WARM GIVEN A
SIMILAR PATTERN AND THE DEW POINTS WILL PROBABLY INCREASE A BIT
MAINLY SUNDAY NIGHT ACROSS THE SOUTHERN AND EASTERN AREAS.
FOR MONDAY AND TUESDAY...AS THE UPPER-LEVEL TROUGH RELOADS FROM THE
WEST, IT MAY SUPPORT WEAK IMPULSES TRAVERSING THE OFFSHORE FRONT. IF
THIS OCCURS AND WITH THE UPPER-LEVEL FLOW TURNING MORE SOUTHWESTERLY
FOR A TIME, THE FRONT MAY INCH BACK INTO OUR AREA TO HELP FOCUS SOME
CONVECTION MONDAY. THIS LOOKS WEAK OVERALL WITH THE MAIN FORCING
REMAINING MOSTLY ACROSS THE GREAT LAKES REGION MONDAY. TIED TO THIS
FORCING, ANOTHER COLD FRONT ARRIVES DURING TUESDAY WITH THE
POTENTIAL FOR SOME CONVECTION ALTHOUGH THE STRONGER SHEAR MAY AGAIN
SLIDE TO OUR NORTH. WE OPTED TO GO CLOSE TO THE 00Z WPC GUIDANCE
WHICH CARRIES POPS OF LOW END CHC OR LESS.
FOR WEDNESDAY...AS THE UPPER-LEVEL TROUGH STARTS TO WEAKEN IN THE
NORTHEAST, THE FRONTAL BOUNDARY FROM TUESDAY SHOULD SLOW OR EVEN
STALL IN OUR VICINITY. THIS COULD HELP FOCUS SOME CONVECTIVE
DEVELOPMENT ESPECIALLY DURING PEAK HEATING, WITH POSSIBLE
CONVECTIVELY INDUCED IMPULSES ARRIVING FROM THE WEST. THERE IS MUCH
MORE UNCERTAINTY THIS FAR OUT AS THE POSITIONING OF THE UPPER-LEVEL
TROUGH WILL GOVERN THE FRONTAL ZONE PLACEMENT AND SUBSEQUENT
CONVECTIVE CHCS.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
PATCHY MVFR CEILINGS WERE LINGERING IN OUR REGION AROUND 1330Z.
THE CLOUDS WILL CONTINUE TO LIFT. SCATTERED CLOUDS OR VFR CEILINGS
ARE ANTICIPATED FOR THE LATE MORNING AND EARLY AFTERNOON HOURS.
SHOWERS AND THUNDERSTORMS, ASSOCIATED WITH AN APPROACHING COLD
FRONT, ARE EXPECTED TO REACH KRDG AND KABE BETWEEN 17-18Z. THE
SHOWERS AND THUNDERSTORMS ARE FORECAST TO REACH KILG, KPHL, KPNE
AND KTTN AROUND 20Z. THEY SHOULD PUSH THROUGH KMIV AND KACY
BETWEEN 22-00Z. CLEARING IS EXPECTED TO OCCUR TONIGHT.
SOUTH TO SOUTHWEST WINDS AROUND 5 TO 10 ARE EXPECTED THROUGH TODAY,
BECOMING NORTHWEST BEHIND THE FRONTAL PASSAGE.
OUTLOOK...
FRIDAY...A CHANCE OF SOME FOG EARLY MAINLY AT KMIV AND KACY,
OTHERWISE VFR. NORTHWEST WINDS AROUND 10 KNOTS, THEN DIMINISHING TO
NEAR 5 KNOTS AT NIGHT AND BECOMING SOUTHWESTERLY.
SATURDAY...VFR OVERALL. A SHOWER OR THUNDERSTORM POSSIBLE IN THE
AFTERNOON AND EVENING MAINLY NORTH AND WEST OF KPHL. SOUTHWEST WINDS
5-10 KNOTS.
SUNDAY AND MONDAY...VFR IS ANTICIPATED.
&&
.MARINE...
A SOUTH TO SOUTHWEST FLOW OF AROUND 10 TO 15 KNOTS WITH GUSTS UP TO
20 KNOTS IS EXPECTED ON THE AREA WATERS THROUGH TONIGHT. SEAS WILL
REMAIN AROUND 2 TO 4 FEET.
A COLD FRONT WILL APPROACH FROM THE WEST AND REACH THE AREA
WATERS LATE TONIGHT. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
PRECEDE THE FRONTAL PASSAGE.
OUTLOOK...
FRIDAY THROUGH MONDAY...THE CONDITIONS ARE ANTICIPATED TO BE BELOW
SMALL CRAFT ADVISORY CRITERIA OVERALL. A LINGERING FRONT OFFSHORE
FRIDAY INTO SATURDAY, THEN ANOTHER FRONT MOVES THROUGH LATE SATURDAY
AND POSSIBLY STALLS NEARBY INTO MONDAY.
&&
.RIP CURRENTS...
A MODERATE RISK OF DANGEROUS RIP CURRENTS IS FORECAST FOR
TODAY, WITH INCREASING SOUTH TO SOUTHWEST FLOW AHEAD OF A COLD
FRONT AND THE FULL MOON ON FRIDAY.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...EXCESSIVE HEAT WARNING UNTIL 6 PM EDT THIS EVENING FOR PAZ070-
071-102-104-106.
NJ...EXCESSIVE HEAT WARNING UNTIL 6 PM EDT THIS EVENING FOR NJZ015-
017>019.
DE...EXCESSIVE HEAT WARNING UNTIL 6 PM EDT THIS EVENING FOR DEZ001.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...GORSE
NEAR TERM...IOVINO/YAROSH
SHORT TERM...MEOLA
LONG TERM...GORSE
AVIATION...GORSE/MEOLA
MARINE...GORSE/MEOLA
RIP CURRENTS...MEOLA
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
857 PM EDT FRI JUL 31 2015
.UPDATE (OVERNIGHT AND SATURDAY)...
00Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS AN AMPLIFIED NORTHERN
STREAM FLOW CONSISTING OF LONGWAVE RIDGING OVER THE PACIFIC
NORTHWEST/WESTERN CANADA AND DOWNSTREAM TROUGHING INTO THE GREAT
LAKES AND NORTHEASTERN STATES. FOLLOWING THE WESTERN RIDGE
SOUTHWARD WE FIND A RIDGE CENTER OVER THE SOUTHWESTERN
STATES/SOUTHERN PLAINS. THIS CIRCULATION OF THIS RIDGE DOES NOT
QUITE REACH OVER TO OUR REGION...AND LEAVES THE FLORIDA PENINSULA
UNDER A MORE ILL-DEFINED MID-LEVEL FLOW REGIME BETWEEN THIS RIDGE
AND ANOTHER LONGWAVE UPPER RIDGE TO THE EAST OF THE BAHAMAS.
WV IMAGERY CONTINUES TO SHOW OUR REGION UNDER ABUNDANT MID/UPPER
LEVEL MOISTURE WHICH IS CONTRIBUTING TO THE EFFICIENT
CONVECTIVE/RAIN PROCESSES. THE 01/00Z SOUNDING IS MOIST THROUGH
THE EXTENT OF THE TROP WITH A PW VALUE NEAR 2" THIS EVENING.
WINDS JUST ABOVE THE SURFACE ARE RATHER BREEZY OFF THE SOUNDING...
AROUND 25-30KTS...AND THIS EXPLAINS THE GUSTY CONDITIONS WE HAVE
SEEN WITH MANY OF THE MORE ORDINARY LOOKING SHOWERS ON RADAR THIS
PAST AFTERNOON/EARLY EVENING.
REST OF THE OVERNIGHT WILL SEE A SCATTERING OF GUSTY
SHOWERS...MAINLY TO THE NORTH OF CHARLOTTE COUNTY...WITH AN
OVERALL DIMINISHMENT IN COVERAGE AS WE HEAD FURTHER INTO THE
EVENING HOURS. ONLY EXCEPTION WILL BE OVER THE NATURE
COAST...MAINLY NORTH OF BROOKSVILLE WHERE THE CLOSER PROXIMITY TO
THE SURFACE TROUGH SHOULD SUPPORT BETTER CHANCES OF CONTINUED
ON AND OFF SHOWERS THROUGH THE OVERNIGHT. WHILE RAIN CHANCES DROP
BELOW THE LIKELY RANGE FOR MOST OF THE AREA WITHIN THE NEXT FEW
HOURS...WILL KEEP 60-70% POPS UP TOWARD CITRUS...AND ESPECIALLY
LEVY THROUGH THE OVERNIGHT.
ALL INDICATIONS FOR SATURDAY ARE THAT THE MOST WIDESPREAD SHOWER
ACTIVITY AND THE POTENTIAL FOR DECENT RAINFALL TOTALS WILL BE
NORTH OF THE I-4 CORRIDOR...AND EVEN NORTH OF A LINE FROM
BROOKSVILLE TO SUMTERVILLE. THIS PATTERN OF SIGNIFICANT RAINFALL
POTENTIAL OVER OUR FAR NORTHERN ZONES ACTUALLY MAY BE THE PATTERN
THROUGH THE UPCOMING WEEKEND. GIVEN THE SOIL MOISTURE AND COLUMN
MOISTURE...WILL STILL BE LOOKING FOR SCT SHOWERS/STORMS FURTHER
SOUTH...BUT APPEARS AS THROUGH THE FURTHER SOUTH ONE TRAVELS...THE
MORE OF A TYPICAL SUMMER PATTERN WILL PRESENT ITSELF COMPARED TO
THE WIDESPREAD SHOWERS/CLOUDS MANY OF US HAVE CONTENDED WITH FOR
MANY DAYS NOW.
THAT BEING SAID...WILL NEED TO KEEP A CLOSE MONITORING ON GUIDANCE
TRENDS FOR THE RAINFALL POTENTIAL OVER OUR FAR NORTHERN
ZONES...CITRUS/LEVY ESPECIALLY. FLOOD WATCHES ARE CURRENTLY IN
EFFECT FOR SATURDAY/SATURDAY NIGHT DOWN THROUGH DIXIE COUNTY TO
THE SUWANNEE RIVER. THE POTENTIAL EXISTS THAT THESE WATCHES WILL
NEED TO BE EXTENDED SOUTH OF THE RIVER INTO LEVY COUNTY
EVENTUALLY. SINCE THERE IS STILL SOME DISAGREEMENT CONCERNING THE
CORRIDOR OF HEAVIEST RAINFALL THE NEXT 72 HOURS...WITH SOME
RELIABLE GUIDANCE MEMBERS KEEPING THE MOST SIGNIFICANT TOTALS
NORTH OF LEVY COUNTY...WILL HOLD OFF ON ANY FLOOD WATCHES AT THIS
TIME. THE OVERNIGHT SHIFT CAN EVALUATE THE NEXT SET OF GUIDANCE
AND MAKE A MORE INFORMED DECISION ON ANY HAZARDS THAT MAY PRESENT
THEMSELVES BY THE END OF THE WEEKEND.
&&
.AVIATION...
A SCATTERING OF SHOWERS WILL CONTINUE TO IMPACT THE TERMINALS
NORTH OF KPGD THIS EVENING...ALTHOUGH THE POTENTIAL FOR HEAVY RAIN
AND GUSTY WINDS IS DIMINISHING. GENERAL VFR CONDITIONS ARE
EXPECTED...ALTHOUGH BRIEF MVFR CIGS/VIS ARE POSSIBLE WITH ANY OF
THE SHOWERS THROUGH 06Z. VFR CONDITIONS WILL BE AROUND THE REGION
ON SATURDAY AWAY FROM SCT SHOWERS. THE BEST CHANCES FOR THE SHOWERS
WILL BE NORTH OF KSRQ...ALTHOUGH THE MOST WIDESPREAD RAINFALL
POTENTIAL APPEARS IT WILL REMAIN NORTH OF THE I-4 CORRIDOR.
&&
.MARINE...
THE FORECAST WATERS WILL REMAIN BETWEEN A TROUGH OF LOW PRESSURE
NEAR THE FLORIDA PANHANDLE AND THE SUBTROPICAL RIDGE AXIS DOWN
TOWARD THE FLORIDA STRAITS THROUGH AT LEAST THE WEEKEND. THE
GRADIENT BETWEEN THESE FEATURES WILL PROVIDE A GENERAL SOUTHWEST
FLOW ACROSS THE EASTERN GULF OF MEXICO. THE GRADIENT WILL BE
STRONGEST OVER THE NORTHEAST GULF AND PROVIDE PERIODS OF
CAUTIONARY LEVEL WINDS OVERNIGHT...MAINLY TO THE NORTH OF TARPON
SPRINGS...AND MAINLY NORTH OF ENGLEWOOD DURING THE DAYLIGHT HOURS
OF SATURDAY. ALTHOUGH SCATTERED SHOWERS AND STORMS WILL BE
POSSIBLE IN ANY OF THE MARINE ZONES...THE MOST WIDESPREAD AND
HEAVY RAINFALL POTENTIAL LOOKS TO EXIST TO THE NORTH OF TARPON
SPRINGS THROUGH THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 77 87 78 88 / 60 50 40 50
FMY 77 92 77 91 / 30 30 20 50
GIF 75 88 75 89 / 70 50 20 70
SRQ 77 88 77 89 / 80 50 30 40
BKV 75 87 74 88 / 60 60 40 60
SPG 78 87 78 88 / 60 50 40 50
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK UNTIL 8 AM EDT SATURDAY FOR COASTAL
CHARLOTTE-COASTAL HILLSBOROUGH-COASTAL LEE-COASTAL
MANATEE-COASTAL SARASOTA-PINELLAS.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION/MARINE...MROCZKA
DECISION SUPPORT...RUDE
UPPER AIR...PAXTON/GUSACK
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
940 AM EDT THU JUL 30 2015
DISCUSSION...
LOW EAST OF GEORGIA/SOUTH CAROLINA WILL CONTINUE TO TRACK AWAY FROM
THE EAST COAST. UPPER LEVEL/500MB TROUGHING BETWEEN UPPER
LEVEL/500MB HIGHS OVER SOUTHERN PLAINS TO THE WEST AND EAST OF THE
BAHAMA ISLANDS EAST IN THE WESTERN ATLANTIC.
LATEST RAP FORECAST RUN SHOWS THE SURFACE LOW CONTINUING TO TRACK
SLOWLY EAST NORTHEAST THE NEXT 12 HOURS. THIS TRACK WILL MAINTAIN
THE OFFSHORE FLOW. LOCAL WRF MODELS SUGGESTING A SEA BREEZE
DEVELOPING FROM CAPE CANAVERAL NORTH WHERE THE OFFSHORE WINDS ARE
FORECAST TO BE LIGHTER. POTENTIAL FOR SOME STRONGER STORMS OVER THE
NORTH FORECAST AREA WHERE SLIGHTLY COOLER UPPER LEVEL TEMPERATURES
RESIDE AND AT THE COAST WHERE THERE MAYBE SEA BREEZE INTERACTING
WITH THE PREVAILING WESTERLY FLOW.
CHANGES TO MAINLY THE VARIOUS WIND GRIDS.
.AVIATION...
PREVAILING VFR THROUGH 18Z. TEMPO MVFR VCTS 19Z-21Z. VFR 31/00Z
THROUGH 31/08Z. TEMPO IFR/MVFR CEILINGS/VISIBILITY 31/08Z-31/14Z DUE
TO LOW CLOUDS/MIST/FOG.
.MARINE...
BUOY 009 WAS RECORDING SOUTHWEST WINDS AROUND 10 KNOTS AND 2 FOOT
SEAS. THE TWO SCRIPPS BUOYS AT 4NM AND 6NM OFF THE BEACH WERE
RECORDING 1 FOOT SEAS.
AFTERNOON SEA BREEZE CAPE CANAVERAL NORTH...OFFSHORE WINDS SOUTH OF
CAPE CANAVERAL AND REMAINDER OF COASTAL WATERS.
PREVIOUS AFD
TODAY-TONIGHT...MODELS SHOW THAT THE AREA OF LOWER PRECIPITABLE
WATER VALUES...THAT SLIPPED INTO NORTHERN AREAS YESTERDAY...
MOISTENING BACK UP ABOVE 2 INCHES. THIS SEEMS REASONABLE AS THE
PERIPHERAL DRYING FROM LOW PRESSURE SYSTEM OFFSHORE NORTH FLORIDA
LIFTS FARTHER AWAY TO THE NORTHEAST.
HAD BEEN A BIT DUBIOUS ABOUT THE 50-70 POPS ADVERTISED BY MOS
ESPECIALLY SINCE THERE WAS CONSIDERABLE DEBRIS CLOUDINESS
OVERSPREADING THE PENINSULA FROM CONVECTION OFFSHORE. RECENT
TRENDS SHOW THE CLOUDS DIMINISHING...AND AS THE LOW PULLS SLOWLY
NORTHEAST...EXPECT THIS TREND TO CONTINUE. THEREFORE MOST PLACES
SHOULD HEAT UP TO AROUND 90 OR THE LOWER 90S. THE MODELS HAVE BEEN
SHOWING TEMPS ALOFT COOLING TO AROUND MINUS 7 CELSIUS. THEREFORE
EXPECT A FEW MORE STRONG STORMS...WITH FREQUENT LIGHTNING STRIKES
BEING THE MAIN DANGER. FORECAST SOUNDINGS SHOW SOME LINGERING
DRIER AIR ALOFT...SO ISOLATED STRONG WIND GUSTS 50-60 MPH COULD
OCCUR AGAIN.
AS FAR AS DISTRIBUTION/TIMING OF THE STORMS...WOULD EXPECT A
GENERAL SCENARIO SIMILAR TO YESTERDAY WITH SHOWERS/STORMS MOVING
ACROSS SOUTHERN SECTIONS EARLIEST (WHERE THE STRONGEST/DEEPEST
WESTERLY FLOW WILL EXIST). THE LOCAL WRF AND HRRR MODELS GENERALLY
SHOW THIS OCCURRING...WITH LATER AND SLOWER MOVING STORMS EXPECTED
ACROSS THE NORTH AS BOUNDARIES INTERACT. THESE STORMS COULD BE
THE STRONGEST OF THE DAY.
MOS HAS POPS 50-60 PERCENT IN THE SOUTH TONIGHT...BUT GIVEN THE
ABOVE DISCUSSION...HAVE TRENDED BELOW THOSE UN-CLIMATOLOGICAL
VALUES.
FRI-FRI NIGHT...WEAK AREA OF LOW PRESSURE AT 500 MB LINGERS OFF OF
THE IMMEDIATE EAST FLORIDA COAST WITH MID-LEVEL HIGH PRESSURE
RIDGING EXTENDING NORTH OF THE AREA ACROSS THE GULF COAST STATES.
AT THE SURFACE HIGH PRESSURE RIDGING REMAINS SUPPRESSED ACROSS THE
SOUTHERN FL PENINSULA/FL STRAITS. A WEAK AREA OF SURFACE LOW
PRESSURE OFF OF THE CAROLINAS EARLY IN THE PERIOD WILL LIFT FAIRLY
RAPIDLY NORTHEASTWARD AWAY FROM THE AREA. DEEP LAYER MOISTURE
CONTINUES WITH PRECIPITABLE WATER VALUES IN EXCESS OF 2 INCHES
ACROSS MUCH OF THE AREA. SUBTLE IMPULSES ALOFT...DEEP MOISTURE AND
BOUNDARY INTERACTIONS THROUGH THE DAY WILL ALLOW FOR HIGH END CHANCE
POPS (50 PERCENT) NEAR I-4 CORRIDOR NORTHWARD (AFTN/EVENING) AND
LIKELY CHANCES (60-70 PERCENT) SOUTHWARD. SCHC/LOW END CHC WORDING
FOR POPS DURING THE MORNING. LOWERING RAIN CHANCES FRI NIGHT THOUGH
REALISTICALLY THERE WILL REMAIN AT LEAST A SLIGHT CHANCE ACROSS ECFL
OVERNIGHT. STORM MOVEMENT MAINLY OUT OF THE SW OR W. HIGHS IN THE
U80S TO AROUND 90 AND LOWS GENERALLY IN THE M/U 70S.
WEEKEND...SURFACE RIDGE AXIS WILL REMAIN SITUATED OVER THE SOUTHERN
FL PENINSULA AS SSW/SW FLOW CONTINUES IN THE LOW-LEVELS. ALOFT...A
GENERALLY TROUGHY PATTERN CONTINUES ALONG THE EASTERN SEABOARD TO
INCLUDE THE FLORIDA PENINSULA. WE ALSO MAINTAIN THE DEEP MOISTURE
AND RELATIVELY WARM TEMPERATURES ALOFT. THE STORM MOTION WHILE WEAK
WILL GENERALLY FAVOR A WEST TO EAST MOVEMENT. LOCALLY HEAVY
RAINFALL...GUSTY WINDS AND CLOUD TO GROUND LIGHTNING WILL REMAIN THE
MAIN CONVECTIVE THREATS. WITH THIS PERSISTENT PATTERN WILL KEEP
LOWER END SCHC/CHC POPS DURING THE MORNING AND MAINLY LIKELY (60
PERCENT) MENTION FOR THE AFTERNOON/EARLY EVENING PERIODS. HIGHS/LOWS
WILL REMAIN CONSISTENT FROM WHAT WE HAVE BEEN SEEING RECENTLY.
MON-WED...ALOFT...AS THE HIGH PRESSURE RIDGING CONTINUES TO AMPLIFY
OVER THE WESTERN U.S. THE GENERAL TROUGHINESS WILL CONTINUE ACROSS
THE EASTERN CONUS. THE SURFACE ATLANTIC RIDGE WILL BEGIN BUILDING
BACK NORTHWARD TUE-WED AS THE EASTERN CONUS LOW-LEVEL TROUGHING
SHIFTS WEST OVER THE GULF OF MEXICO. EXPECT MOISTURE TO REMAIN HIGH
AND POPS 50 PERCENT OR A LITTLE HIGHER STILL SEEM WARRANTED...EXCEPT
POSSIBLY TRENDING LOWER WED...IF THE SURFACE RIDGE DOES INDEED BUILD
BACK INTO CENTRAL FLORIDA.
&&
.AVIATION...A FEW MVFR CEILINGS WILL OCCUR UNTIL A LITTLE AFTER
SUNRISE. THERE IS A LITTLE MORE LOW LEVEL WIND THIS MORNING...BUT
LOCAL IFR COULD BRIEFLY OCCUR TOO. THEN THE MAIN FORECAST PROBLEM
BECOMES THE TIMING OF STORMS. EXPECT THAT FROM ABOUT KVRB-KSUA
THERE WILL BE A CHANCE FOR STORMS RATHER EARLY AGAIN...ABOUT
16-20Z...WITH THE REMAINING TERMINALS LIKELY HAVING THE GREATEST
CHANCE BETWEEN 18-22Z. A FEW STRONG STORMS WITH WIND FREQUENT
LIGHTNING STRIKES AND GUSTY WINDS OVER 30 KNOTS ARE EXPECTED AGAIN.
&&
.MARINE...
TODAY-TONIGHT...SOUTHWEST WIND FLOW REGIME WILL CONTINUE WITH
SPEEDS 10-15 KNOTS OFFSHORE AND 5-10 KNOTS CLOSE TO THE COAST. THE
MAIN MARINER CONCERN WILL BE OFFSHORE MOVING SHOWERS/STORMS WHICH
COULD MOVE OFFSHORE THE TREASURE COAST BY EARLY AFTERNOON.
STEERING FLOW WILL BE WEAK NORTHWARD TO THE VOLUSIA COAST...BUT A
FEW STRONG STORMS COULD AFFECT THE NEARSHORE WATERS LATE IN THE
AFTERNOON.
FRI-FRI NIGHT...SURFACE RIDGE AXIS REMAINS SUPPRESSED TO THE SOUTH.
MAINLY SSW/SW WINDS AROUND 10 KTS. SEAS GENERALLY AOB 3 FT.
WINDS/SEAS LOCALLY HIGHER INVOF OF STRONGER CONVECTION. OFFSHORE
MOVING STORM CELLS REMAIN A THREAT THROUGH THE PERIOD. COVERAGE OF
SHOWERS/STORMS LOOKS RATHER HIGH AND STORMS SHOULD START TO PRODUCE
MORE FREQUENT LIGHTNING STRIKES.
SAT-MON...SURFACE RIDGE AXIS ACROSS THE SOUTHERN PENINSULA INTO
EARLY NEXT WEEK. LITTLE CHANGE IN MOIST SSW/SW WIND FLOW REGIME.
STORM MOTION STILL OFFSHORE BUT WEAKER. BOATERS SHOULD CONTINUE TO
BE VIGILANT FOR MARINE STORMS... ESPECIALLY DURING THE AFTERNOON AND
EVENING. WIND SPEEDS AOB 15 KTS WITH SEAS 2-4 FT GENERALLY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 90 74 90 74 / 60 30 50 30
MCO 91 74 90 74 / 60 30 50 30
MLB 91 73 89 74 / 60 30 60 40
VRB 90 73 89 72 / 60 30 70 40
LEE 89 76 91 76 / 60 30 50 30
SFB 92 75 91 74 / 60 30 50 30
ORL 91 76 90 75 / 60 30 50 30
FPR 90 73 89 73 / 60 30 70 40
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
IMPACT WX...CRISTALDI
FORECASTS...WIMMER
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
341 AM EDT THU JUL 30 2015
.DISCUSSION...
TODAY-TONIGHT...MODELS SHOW THAT THE AREA OF LOWER PRECIPITABLE
WATER VALUES...THAT SLIPPED INTO NORTHERN AREAS YESTERDAY...
MOISTENING BACK UP ABOVE 2 INCHES. THIS SEEMS REASONABLE AS THE
PERIPHERAL DRYING FROM LOW PRESSURE SYSTEM OFFSHORE NORTH FLORIDA
LIFTS FARTHER AWAY TO THE NORTHEAST.
HAD BEEN A BIT DUBIOUS ABOUT THE 50-70 POPS ADVERTISED BY MOS
ESPECIALLY SINCE THERE WAS CONSIDERABLE DEBRIS CLOUDINESS
OVERSPREADING THE PENINSULA FROM CONVECTION OFFSHORE. RECENT
TRENDS SHOW THE CLOUDS DIMINISHING...AND AS THE LOW PULLS SLOWLY
NORTHEAST...EXPECT THIS TREND TO CONTINUE. THEREFORE MOST PLACES
SHOULD HEAT UP TO AROUND 90 OR THE LOWER 90S. THE MODELS HAVE BEEN
SHOWING TEMPS ALOFT COOLING TO AROUND MINUS 7 CELSIUS. THEREFORE
EXPECT A FEW MORE STRONG STORMS...WITH FREQUENT LIGHTNING STRIKES
BEING THE MAIN DANGER. FORECAST SOUNDINGS SHOW SOME LINGERING
DRIER AIR ALOFT...SO ISOLATED STRONG WIND GUSTS 50-60 MPH COULD
OCCUR AGAIN.
AS FAR AS DISTRIBUTION/TIMING OF THE STORMS...WOULD EXPECT A
GENERAL SCENARIO SIMILAR TO YESTERDAY WITH SHOWERS/STORMS MOVING
ACROSS SOUTHERN SECTIONS EARLIEST (WHERE THE STRONGEST/DEEPEST
WESTERLY FLOW WILL EXIST). THE LOCAL WRF AND HRRR MODELS GENERALLY
SHOW THIS OCCURRING...WITH LATER AND SLOWER MOVING STORMS EXPECTED
ACROSS THE NORTH AS BOUNDARIES INTERACT. THESE STORMS COULD BE
THE STRONGEST OF THE DAY.
MOS HAS POPS 50-60 PERCENT IN THE SOUTH TONIGHT...BUT GIVEN THE
ABOVE DISCUSSION...HAVE TRENDED BELOW THOSE UN-CLIMATOLOGICAL
VALUES.
FRI-FRI NIGHT...WEAK AREA OF LOW PRESSURE AT 500 MB LINGERS OFF OF
THE IMMEDIATE EAST FLORIDA COAST WITH MID-LEVEL HIGH PRESSURE
RIDGING EXTENDING NORTH OF THE AREA ACROSS THE GULF COAST STATES.
AT THE SURFACE HIGH PRESSURE RIDGING REMAINS SUPPRESSED ACROSS THE
SOUTHERN FL PENINSULA/FL STRAITS. A WEAK AREA OF SURFACE LOW
PRESSURE OFF OF THE CAROLINAS EARLY IN THE PERIOD WILL LIFT FAIRLY
RAPIDLY NORTHEASTWARD AWAY FROM THE AREA. DEEP LAYER MOISTURE
CONTINUES WITH PRECIPITABLE WATER VALUES IN EXCESS OF 2 INCHES
ACROSS MUCH OF THE AREA. SUBTLE IMPULSES ALOFT...DEEP MOISTURE AND
BOUNDARY INTERACTIONS THROUGH THE DAY WILL ALLOW FOR HIGH END CHANCE
POPS (50 PERCENT) NEAR I-4 CORRIDOR NORTHWARD (AFTN/EVENING) AND
LIKELY CHANCES (60-70 PERCENT) SOUTHWARD. SCHC/LOW END CHC WORDING
FOR POPS DURING THE MORNING. LOWERING RAIN CHANCES FRI NIGHT THOUGH
REALISTICALLY THERE WILL REMAIN AT LEAST A SLIGHT CHANCE ACROSS ECFL
OVERNIGHT. STORM MOVEMENT MAINLY OUT OF THE SW OR W. HIGHS IN THE
U80S TO AROUND 90 AND LOWS GENERALLY IN THE M/U 70S.
WEEKEND...SURFACE RIDGE AXIS WILL REMAIN SITUATED OVER THE SOUTHERN
FL PENINSULA AS SSW/SW FLOW CONTINUES IN THE LOW-LEVELS. ALOFT...A
GENERALLY TROUGHY PATTERN CONTINUES ALONG THE EASTERN SEABOARD TO
INCLUDE THE FLORIDA PENINSULA. WE ALSO MAINTAIN THE DEEP MOISTURE
AND RELATIVELY WARM TEMPERATURES ALOFT. THE STORM MOTION WHILE WEAK
WILL GENERALLY FAVOR A WEST TO EAST MOVEMENT. LOCALLY HEAVY
RAINFALL...GUSTY WINDS AND CLOUD TO GROUND LIGHTNING WILL REMAIN THE
MAIN CONVECTIVE THREATS. WITH THIS PERSISTENT PATTERN WILL KEEP
LOWER END SCHC/CHC POPS DURING THE MORNING AND MAINLY LIKELY (60
PERCENT) MENTION FOR THE AFTERNOON/EARLY EVENING PERIODS. HIGHS/LOWS
WILL REMAIN CONSISTENT FROM WHAT WE HAVE BEEN SEEING RECENTLY.
MON-WED...ALOFT...AS THE HIGH PRESSURE RIDGING CONTINUES TO AMPLIFY
OVER THE WESTERN U.S. THE GENERAL TROUGHINESS WILL CONTINUE ACROSS
THE EASTERN CONUS. THE SURFACE ATLANTIC RIDGE WILL BEGIN BUILDING
BACK NORTHWARD TUE-WED AS THE EASTERN CONUS LOW-LEVEL TROUGHING
SHIFTS WEST OVER THE GULF OF MEXICO. EXPECT MOISTURE TO REMAIN HIGH
AND POPS 50 PERCENT OR A LITTLE HIGHER STILL SEEM WARRANTED...EXCEPT
POSSIBLY TRENDING LOWER WED...IF THE SURFACE RIDGE DOES INDEED BUILD
BACK INTO CENTRAL FLORIDA.
&&
.AVIATION...A FEW MVFR CEILINGS WILL OCCUR UNTIL A LITTLE AFTER
SUNRISE. THERE IS A LITTLE MORE LOW LEVEL WIND THIS MORNING...BUT
LOCAL IFR COULD BRIEFLY OCCUR TOO. THEN THE MAIN FORECAST PROBLEM
BECOMES THE TIMING OF STORMS. EXPECT THAT FROM ABOUT KVRB-KSUA
THERE WILL BE A CHANCE FOR STORMS RATHER EARLY AGAIN...ABOUT
16-20Z...WITH THE REMAINING TERMINALS LIKELY HAVING THE GREATEST
CHANCE BETWEEN 18-22Z. A FEW STRONG STORMS WITH WIND FREQUENT
LIGHTNING STRIKES AND GUSTY WINDS OVER 30 KNOTS ARE EXPECTED AGAIN.
&&
.MARINE...
TODAY-TONIGHT...SOUTHWEST WIND FLOW REGIME WILL CONTINUE WITH
SPEEDS 10-15 KNOTS OFFSHORE AND 5-10 KNOTS CLOSE TO THE COAST. THE
MAIN MARINER CONCERN WILL BE OFFSHORE MOVING SHOWERS/STORMS WHICH
COULD MOVE OFFSHORE THE TREASURE COAST BY EARLY AFTERNOON.
STEERING FLOW WILL BE WEAK NORTHWARD TO THE VOLUSIA COAST...BUT A
FEW STRONG STORMS COULD AFFECT THE NEARSHORE WATERS LATE IN THE
AFTERNOON.
FRI-FRI NIGHT...SURFACE RIDGE AXIS REMAINS SUPPRESSED TO THE SOUTH.
MAINLY SSW/SW WINDS AROUND 10 KTS. SEAS GENERALLY AOB 3 FT.
WINDS/SEAS LOCALLY HIGHER INVOF OF STRONGER CONVECTION. OFFSHORE
MOVING STORM CELLS REMAIN A THREAT THROUGH THE PERIOD. COVERAGE OF
SHOWERS/STORMS LOOKS RATHER HIGH AND STORMS SHOULD START TO PRODUCE
MORE FREQUENT LIGHTNING STRIKES.
SAT-MON...SURFACE RIDGE AXIS ACROSS THE SOUTHERN PENINSULA INTO
EARLY NEXT WEEK. LITTLE CHANGE IN MOIST SSW/SW WIND FLOW REGIME.
STORM MOTION STILL OFFSHORE BUT WEAKER. BOATERS SHOULD CONTINUE TO
BE VIGILANT FOR MARINE STORMS... ESPECIALLY DURING THE AFTERNOON AND
EVENING. WIND SPEEDS AOB 15 KTS WITH SEAS 2-4 FT GENERALLY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 90 74 90 74 / 60 30 50 30
MCO 91 74 90 74 / 60 30 50 30
MLB 91 73 89 74 / 60 30 60 40
VRB 90 73 89 72 / 60 30 70 40
LEE 89 76 91 76 / 60 30 50 30
SFB 92 75 91 74 / 60 30 50 30
ORL 91 76 90 75 / 60 30 50 30
FPR 90 73 89 73 / 60 30 70 40
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...LASCODY
LONG TERM....SEDLOCK
AREA FORECAST DISCUSSION
NWS LINCOLN IL
858 PM CDT FRI JUL 31 2015
.UPDATE...
ISSUED AT 858 PM CDT FRI JUL 31 2015
A FEW ISOLATED THUNDERSTORMS HAVE MANAGED TO FORM ALONG A STALLED
FRONTAL BOUNDARY IN FAR WEST-CENTRAL IL AND COULD REACH INTO
SCHUYLER...CASS...SCOTT...AND MORGAN COUNTIES THIS EVENING. CLOUD
COVER ASSOCIATED WITH STORMS FORMING ALONG THE BOUNDARY TOWARD THE
WEST OVER THE MISSOURI/IOWA BORDER CONTINUE TO SPREAD ACROSS THE
SOUTHERN PORTIONS OF THE CENTRAL IL FORECAST AREA. HAVE UPDATED
FORECASTS FOR THESE TRENDS. OTHERWISE...FORECAST IS ON TRACK FOR A
MOSTLY CLEAR NIGHT ONCE THE CLOUD BAND SLIPS SOUTHWARD...WITH
LOWS REACHING THE LOW TO MID 60S AND LIGHT WEST-NORTHWEST WINDS.
&&
.SHORT TERM...(TONIGHT)
ISSUED AT 315 PM CDT FRI JUL 31 2015
19Z/2PM SURFACE ANALYSIS SHOWS WEAK COLD FRONT SETTLING INTO CENTRAL
ILLINOIS...EXTENDING FROM NEAR RANTOUL TO JUST SOUTH OF QUINCY.
MINIMAL CONVERGENCE ALONG THE FRONT AND AN OVERALL LACK OF DEEP
LAYER MOISTURE HAS LARGELY PREVENTED CONVECTION. THE EXCEPTION HAS
BEEN FURTHER NORTHEAST ACROSS NORTHERN INDIANA WHERE A FEW CLUSTERS
OF THUNDERSTORMS HAVE DEVELOPED. HRRR CONTINUES TO OVER-EMPHASIZE
DEWPOINT POOLING ALONG THE FRONT AND PRODUCES NUMEROUS THUNDERSTORMS
WITH ITS 1 AND 2-HOUR FORECAST. MEANWHILE...THE RAPID REFRESH HAS
CONSISTENTLY PRESENTED A MORE REALISTIC SCENARIO...SUGGESTING ONLY
ISOLATED STORMS MAINLY ACROSS THE E/NE KILX CWA OVER THE NEXT 2-4
HOURS. GIVEN THIS IS THE LOCATION WHERE CU-FIELD IS CURRENTLY MOST
PRONOUNCED...WILL CONTINUE TO FOLLOW THIS SOLUTION CLOSELY. AS A
RESULT...WILL CARRY SLIGHT CHANCE POPS ALONG/NORTHEAST OF A
CHAMPAIGN TO MARSHALL LINE THROUGH THE AFTERNOON. ANY ISOLATED
CONVECTION THAT DEVELOPS WILL QUICKLY DISSIPATE TOWARD
SUNSET...FOLLOWED BY MOSTLY CLEAR AND DRY CONDITIONS TONIGHT.
SLIGHTLY DRIER AIRMASS WILL TRICKLE IN FROM THE NORTHWEST ONCE THE
FRONT PASSES...WITH OVERNIGHT LOW TEMPERATURES DROPPING INTO THE
LOWER TO MIDDLE 60S.
.LONG TERM...(SATURDAY THROUGH FRIDAY)
ISSUED AT 315 PM CDT FRI JUL 31 2015
OVERALL A FAIRLY PERSISTENT WNW FLOW PATTERN WILL REMAIN ACROSS IL
AND MUCH OF THE MIDWEST THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK. QUITE A BIT OF MODEL UNCERTAINTY REGARDING A BREAKDOWN OF THE
WESTERN RIDGE AND DEEPENING OF THE EASTERN TROUGH FOR THE MIDDLE OF
NEXT WEEK.
IN THE NEAR TERM...VERY WARM AND INCREASINGLY HUMID CONDITIONS WILL
BE ON TAP FOR CENTRAL AND EASTERN IL SATURDAY. AN ADVANCING WARM
FRONT AND A CLUSTER OF CONVECTION FROM IOWA/NEBRASKA IS EXPECTED TO
APPROACH AREAS WEST OF THE IL RIVER VALLEY LATE SATURDAY NIGHT AND
INTO SUNDAY MORNING. THE REMNANTS OF THE EARLY MORNING T-STORMS ARE
THEN EXPECTED TO SPREAD ACROSS MOST OF CENTRAL AND EASTERN IL SUNDAY
MORNING AND EARLY AFTERNOON. RESIDUAL BOUNDARIES FROM THIS
CONVECTION SHOULD RESULT IN REDEVELOPMENT OF T-STORMS SUNDAY
AFTERNOON AND INTO THE EVENING...ESPECIALLY ALONG AND NORTH OF I-74.
SOME OF THE STORMS LATER IN THE DAY SUNDAY COULD BE STRONG...MAINLY
DUE TO MODERATE LEVELS OF WIND SHEAR AND INSTABILITY.
MOST OF THE FORECAST AREA WILL BE IN THE WARM SECTOR OF AN ADVANCING
FRONTAL BOUNDARY...YIELDING VERY WARM AND SOMEWHAT HUMID CONDITIONS
MONDAY. THE AFOREMENTIONED FRONT IS EXPECTED TO SLOWLY MOVE INTO
CENTRAL ILLINOIS MONDAY NIGHT AND THEN REMAIN NEARLY STATIONARY FOR
MUCH OF THE WEEK. THIS SHOULD RESULT IN A RATHER UNSETTLED WEATHER
PATTERN WITH THE POTENTIAL FOR SEVERAL PERIODS OF RAIN FROM LATE
MONDAY...ON AND OFF...THROUGH THE END OF THE WEEK.
THE UNCERTAINTY IN THE MODELS REVOLVES AROUND THE DETAILS OF
POSSIBLE SHORTWAVE ENERGY BREAKING THROUGH THE WESTERN U.S. RIDGE
AND INTERACTING WITH THE FRONT. THE GFS IS A BIT MORE AGGRESSIVE WITH
THIS THAN THE EUROPEAN MODEL. HOWEVER...THE EUROPEAN NOT ONLY
UNDERPLAYS THE AFFECTS OF THIS BUT KEEPS THE SURFACE FRONT FARTHER
NORTH. UNTIL THE DETAILS ARE WORKED OUT IT IS HARD TO PIN DOWN
WHERE A THREAT OF PERSISTENT...POSSIBLY HEAVY RAIN MAY SET UP THE
MIDDLE OF NEXT WEEK. THUS...WILL NOT MAKE TOO MANY MAJOR CHANGES
TO THE FORECAST AND KEEP CHANCE POPS FOR THUNDERSTORMS ACROSS A
LARGE PART OF THE FORECAST AREA.
THE ONE THING THE MODELS DO AGREE ON IS THAT WITH THE PERIODS OF
CONVECTION AND RESIDUAL CLOUD COVER...TEMPERATURES SHOULD BE BELOW
SEASONAL NORMALS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 641 PM CDT FRI JUL 31 2015
VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24 HOURS AS HIGH
PRESSURE CONTINUES OVER THE AREA WITH A FRONTAL BOUNDARY PUSHED
JUST SOUTH OF THE CENTRAL IL TERMINALS. CONVECTION OVER NW
MISSOURI/SW IOWA THIS EVENING WILL CAUSE SOME MID AND HIGH CLOUD
COVER TO DRIFT EASTWARD OVER THE SOUTHERN TERMINALS KSPI-
KDEC...BUT DRY CONDITIONS AND VFR FLIGHT CATEGORY WILL CONTINUE.
WINDS WNW 3-5 KTS OVERNIGHT...BECOMING SW 8-12 KTS AFTER 15Z
SATURDAY.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ONTON
SHORT TERM...BARNES
LONG TERM...MILLER
AVIATION...ONTON
AREA FORECAST DISCUSSION
NWS LINCOLN IL
641 PM CDT FRI JUL 31 2015
.SHORT TERM...(TONIGHT)
ISSUED AT 315 PM CDT FRI JUL 31 2015
19Z/2PM SURFACE ANALYSIS SHOWS WEAK COLD FRONT SETTLING INTO CENTRAL
ILLINOIS...EXTENDING FROM NEAR RANTOUL TO JUST SOUTH OF QUINCY.
MINIMAL CONVERGENCE ALONG THE FRONT AND AN OVERALL LACK OF DEEP
LAYER MOISTURE HAS LARGELY PREVENTED CONVECTION. THE EXCEPTION HAS
BEEN FURTHER NORTHEAST ACROSS NORTHERN INDIANA WHERE A FEW CLUSTERS
OF THUNDERSTORMS HAVE DEVELOPED. HRRR CONTINUES TO OVER-EMPHASIZE
DEWPOINT POOLING ALONG THE FRONT AND PRODUCES NUMEROUS THUNDERSTORMS
WITH ITS 1 AND 2-HOUR FORECAST. MEANWHILE...THE RAPID REFRESH HAS
CONSISTENTLY PRESENTED A MORE REALISTIC SCENARIO...SUGGESTING ONLY
ISOLATED STORMS MAINLY ACROSS THE E/NE KILX CWA OVER THE NEXT 2-4
HOURS. GIVEN THIS IS THE LOCATION WHERE CU-FIELD IS CURRENTLY MOST
PRONOUNCED...WILL CONTINUE TO FOLLOW THIS SOLUTION CLOSELY. AS A
RESULT...WILL CARRY SLIGHT CHANCE POPS ALONG/NORTHEAST OF A
CHAMPAIGN TO MARSHALL LINE THROUGH THE AFTERNOON. ANY ISOLATED
CONVECTION THAT DEVELOPS WILL QUICKLY DISSIPATE TOWARD
SUNSET...FOLLOWED BY MOSTLY CLEAR AND DRY CONDITIONS TONIGHT.
SLIGHTLY DRIER AIRMASS WILL TRICKLE IN FROM THE NORTHWEST ONCE THE
FRONT PASSES...WITH OVERNIGHT LOW TEMPERATURES DROPPING INTO THE
LOWER TO MIDDLE 60S.
.LONG TERM...(SATURDAY THROUGH FRIDAY)
ISSUED AT 315 PM CDT FRI JUL 31 2015
OVERALL A FAIRLY PERSISTENT WNW FLOW PATTERN WILL REMAIN ACROSS IL
AND MUCH OF THE MIDWEST THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK. QUITE A BIT OF MODEL UNCERTAINTY REGARDING A BREAKDOWN OF THE
WESTERN RIDGE AND DEEPENING OF THE EASTERN TROUGH FOR THE MIDDLE OF
NEXT WEEK.
IN THE NEAR TERM...VERY WARM AND INCREASINGLY HUMID CONDITIONS WILL
BE ON TAP FOR CENTRAL AND EASTERN IL SATURDAY. AN ADVANCING WARM
FRONT AND A CLUSTER OF CONVECTION FROM IOWA/NEBRASKA IS EXPECTED TO
APPROACH AREAS WEST OF THE IL RIVER VALLEY LATE SATURDAY NIGHT AND
INTO SUNDAY MORNING. THE REMNANTS OF THE EARLY MORNING T-STORMS ARE
THEN EXPECTED TO SPREAD ACROSS MOST OF CENTRAL AND EASTERN IL SUNDAY
MORNING AND EARLY AFTERNOON. RESIDUAL BOUNDARIES FROM THIS
CONVECTION SHOULD RESULT IN REDEVELOPMENT OF T-STORMS SUNDAY
AFTERNOON AND INTO THE EVENING...ESPECIALLY ALONG AND NORTH OF I-74.
SOME OF THE STORMS LATER IN THE DAY SUNDAY COULD BE STRONG...MAINLY
DUE TO MODERATE LEVELS OF WIND SHEAR AND INSTABILITY.
MOST OF THE FORECAST AREA WILL BE IN THE WARM SECTOR OF AN ADVANCING
FRONTAL BOUNDARY...YIELDING VERY WARM AND SOMEWHAT HUMID CONDITIONS
MONDAY. THE AFOREMENTIONED FRONT IS EXPECTED TO SLOWLY MOVE INTO
CENTRAL ILLINOIS MONDAY NIGHT AND THEN REMAIN NEARLY STATIONARY FOR
MUCH OF THE WEEK. THIS SHOULD RESULT IN A RATHER UNSETTLED WEATHER
PATTERN WITH THE POTENTIAL FOR SEVERAL PERIODS OF RAIN FROM LATE
MONDAY...ON AND OFF...THROUGH THE END OF THE WEEK.
THE UNCERTAINTY IN THE MODELS REVOLVES AROUND THE DETAILS OF
POSSIBLE SHORTWAVE ENERGY BREAKING THROUGH THE WESTERN U.S. RIDGE
AND INTERACTING WITH THE FRONT. THE GFS IS A BIT MORE AGGRESSIVE WITH
THIS THAN THE EUROPEAN MODEL. HOWEVER...THE EUROPEAN NOT ONLY
UNDERPLAYS THE AFFECTS OF THIS BUT KEEPS THE SURFACE FRONT FARTHER
NORTH. UNTIL THE DETAILS ARE WORKED OUT IT IS HARD TO PIN DOWN
WHERE A THREAT OF PERSISTENT...POSSIBLY HEAVY RAIN MAY SET UP THE
MIDDLE OF NEXT WEEK. THUS...WILL NOT MAKE TOO MANY MAJOR CHANGES
TO THE FORECAST AND KEEP CHANCE POPS FOR THUNDERSTORMS ACROSS A
LARGE PART OF THE FORECAST AREA.
THE ONE THING THE MODELS DO AGREE ON IS THAT WITH THE PERIODS OF
CONVECTION AND RESIDUAL CLOUD COVER...TEMPERATURES SHOULD BE BELOW
SEASONAL NORMALS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 641 PM CDT FRI JUL 31 2015
VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24 HOURS AS HIGH
PRESSURE CONTINUES OVER THE AREA WITH A FRONTAL BOUNDARY PUSHED
JUST SOUTH OF THE CENTRAL IL TERMINALS. CONVECTION OVER NW
MISSOURI/SW IOWA THIS EVENING WILL CAUSE SOME MID AND HIGH CLOUD
COVER TO DRIFT EASTWARD OVER THE SOUTHERN TERMINALS KSPI-
KDEC...BUT DRY CONDITIONS AND VFR FLIGHT CATEGORY WILL CONTINUE.
WINDS WNW 3-5 KTS OVERNIGHT...BECOMING SW 8-12 KTS AFTER 15Z
SATURDAY.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BARNES
LONG TERM...MILLER
AVIATION...ONTON
AREA FORECAST DISCUSSION
NWS DES MOINES IA
359 PM CDT THU JUL 30 2015
.SHORT TERM /TONIGHT/...
ISSUED AT 357 PM CDT THU JUL 30 2015
SURFACE HIGH WILL REMAIN IN PLACE OVER FAR SOUTHERN IOWA TONIGHT
WHILE ALOFT WE WILL REMAIN IN NORTHWEST FLOW. THE NAM IS SUGGESTING
A SUBTLE SHORTWAVE CROSSING SOUTHWEST IOWA OVERNIGHT AS A WEAK COLD
FRONT SINKS INTO THE NORTHWEST QUARTER OR SO OF THE STATE. THERE IS
SOME POSSIBILITY THAT A SPRINKLE OR TWO COULD BE ASSOCIATED WITH
EITHER OF THESE FEATURES BUT INSTABILITY IS RATHER MINIMAL AND
FORCING IS TIED MORE TO THE FRONTAL BOUNDARY THAN THE SUBTLE WAVE
ACROSS THE SOUTH...WHERE THE BETTER INSTABILITY LIES. CONFIDENCE AS
TO WHERE ANY PRECIP MAY OCCUR IS VERY LOW AND AS SUCH I DO NOT HAVE
A MENTION OF POPS IN THE FORECAST. HI-RES CONVECTION ALLOWING
MODELS ARE IN POOR AGREEMENT AS WELL AS THE HRRR CURRENTLY IS
FORECASTING SHOWERS ACROSS THE NORTHERN HALF OF IOWA WHERE THERE ARE
BARELY A FEW CLOUDS. THE NAM 12 HAS SPITS OF PRECIP OVER BOTH THE
SOUTH AND NORTHWEST WHILE THE OTHER MODELS DO THIS OVER THE SOUTH.
COVERAGE WOULD BE SPARSE AND POPS MAY NEED TO BE ADJUSTED IN LATER
SHIFTS IF SOMETHING IS ABLE TO DEVELOP. AS FOR TEMPS...NORTHWEST
IOWA SHOULD BE THE COOLEST AS THE FRONT WILL BE THROUGH THEM BUT IT
IS DOUBTFUL THAT IT WILL MAKE IT TOO FAR INTO OUR FORECAST AREA BY
12Z. AS A RESULT I HAVE KEPT LOWER 60S NORTH TO MID 60S SOUTH FOR
TONIGHT`S LOWS.
.LONG TERM /FRIDAY THROUGH THURSDAY/...
ISSUED AT 357 PM CDT THU JUL 30 2015
GENERAL PREMISE OF LONG TERM LOOKING SIMILAR TO YESTERDAY/S OUTPUT.
DIFFERENCE IS THAT TODAY/S RUNS ARE A LITTLE MORE AMPLIFIED AND
CONFIDENCE INCREASED IN MULTIPLE ROUND OF PRECIP OF THE NEXT SEVEN
DAYS. FROM 12Z UNTIL 18Z FRIDAY...A WEAK BOUNDARY WILL BE PASSING
THROUGH OUR CWA FROM NW TO SE. PWATS WITH THIS BOUNDARY BARELY GO
ABOVE 1 INCH AND MOISTURE CONV AT THE SFC IS MINIMAL. TIME OF DAY
ALSO TYPICALLY NOT FAVORABLE FOR CONVECTION. THEREFORE...AM
KEEPING CWA DRY WITH THIS BOUNDARY PASSAGE. EXPECT ANOTHER MAINLY
CLOUD- FREE DAY WITH 850MB TEMPS IN THE 17C TO 20C RANGE TO MIX
DOWN AND YIELD MID TO UPPER 80S.
FRIDAY EVENING INTO SATURDAY MORNING...THE AFOREMENTIONED BOUNDARY
LOOKS TO LINGER IN NORTHERN MISSOURI TO NORTHEASTERN NEBRASKA AND
WILL SERVE AS THE FOCUSING MECHANISM FOR EVENING
CONVECTION...ESPECIALLY IN NORTHEASTERN NEBRASKA. CORFIDI VECTORS
SUGGEST STORM MOVEMENT WILL BE TO THE SE...WITH ANY RIGHT-MOVERS
MOVING MORE SOUTHERLY. WITH ENOUGH INSTABILITY PRESENT IN SOUTHERN
IOWA AHEAD OF THESE STORMS...IT SEEMS PLAUSIBLE ANY OUTFLOW
BOUNDARIES WILL PROPAGATE IN A NE/E DIRECTION INTO SOUTHERN
IOWA...POSSIBLY CLIPPING OUR SW COUNTIES. THEREFORE HAVE SOME
SLIGHT POPS GOING IN OUR SOUTH WHICH CAN OBVIOUSLY BE TWEAKED IN
NEXT UPDATES.
SATURDAY LOOKS TO BE DRY...BUT THE NEXT PRECIP CHANCES FOR ARRIVE
LATE EVENING INTO THE OVERNIGHT PERIOD FOR SUNDAY MORNING. MODELS
NOW VERY CONSISTENT IN PRODUCING A SIZABLE MCS OVER SE SOUTH DAKOTA
AND PROPAGATING THIS MCS SOUTHEASTWARD THROUGH THE CENTRAL TO
WESTERN PORTIONS OF OUR CWA. GFS SEEMING TO BE A FAST OUTLIER...SO
LEANED AWAY FROM IT FOR TIMING PURPOSES. AM STARTING TO SEE HEAVY
RAINFALL SIGNATURE AS SHORT TERM MODELS PLACING A SLUG OF 2 TO 2.25
INCH PWATS WITH THIS MCS...MIXING RATIOS OVER 8 J/KG...AND 0 TO 6 MU
CAPE OVER 1500 J/KG. IN FACT THE 18Z NAM HAD PWATS OVER 2.5
INCHES...SO RECENT MODEL TRENDS CERTAINLY POINTING UPWARDS.
BEYOND SUNDAY...YESTERDAY/S LONG TERM MODELS HINTED AT A
BAROCLINIC ZONE TRYING TO ESTABLISH ITSELF OVER OUR SOUTHERN CWA
THROUGH MID WEEK. REGION TO REMAIN IN WESTERLY TO NORTHWESTERLY
FLOW ALOFT...SUGGESTING AN OVERALL PATTERN OF SHORTWAVE
PROPAGATION THROUGH IOWA. TODAY/S MODEL RUNS YIELD A SIMILAR
SETUP TO YESTERDAY/S...WITH THE MAIN DIFFERENCE BEING HIGHER PWATS
IN THE 1.5 INCH RANGE OR SO OVER MUCH OF OUR CWA. THUS...HAVE
INCREASED POPS FURTHER NORTH FROM YESTERDAY AND UPPED CONFIDENCE
SLIGHTLY. INTERESTING THAT THE GFS...WHICH OFTEN HAS A DRY
BIAS...IS PRODUCING SO MUCH MOISTURE IN IOWA. IF UPWARD TREND
CONTINUES...NEXT WEEK COULD BE WET. WITH EXPECTED CLOUD
COVER...BEGUN TO TRIM DIURNAL RANGE...SLIGHTLY LOWERING MAX TEMPS
AND INCREASING MIN TEMPS.
&&
.AVIATION...30/18Z
ISSUED AT 1210 PM CDT THU JUL 30 2015
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. WARM ADVECTION WILL
BE RESPONSIBLE FOR SOME SCT MID/HIGH LEVEL CLOUDS. AFT 03Z A WEAK
COLD FRONT WILL SINK SOUTH ACROSS THE TAF LOCATIONS. THIS WILL
BRING A SCT-BKN DECK BTWN 080-100KFT WHICH IS EXPECTED TO DIMINISH
LATE IN THE FCST PD. SFC WND WILL BECOME NW AFT 03Z WITH THE FROPA
AND MAY INCREASE AFT 13Z TO 10-15KTS.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...FAB
LONG TERM...KOTENBERG
AVIATION...FAB
AREA FORECAST DISCUSSION
NWS GOODLAND KS
539 PM MDT FRI JUL 31 2015
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 141 PM MDT FRI JUL 31 2015
PERSISTENT UPPER LEVEL RIDGE CONTINUES TO DOMINATE PATTERN ACROSS
WESTERN US THROUGH THE SOUTHERN PLAINS...WITH NW FLOW ACROSS THE
NORTHERN PLAINS. WV IMAGERY SHOWS MONSOONAL MOISTURE PLUME EXTENDING
FROM THE BAJA PENINSULA ACROSS THE FOUR CORNER AND INTO THE HIGH
PLAINS WITH SEVERAL WEAK SHORTWAVE TROUGHS ROTATING AROUND RIDGE
INTO THE SOUTHERN PLAINS AND THROUGH THE NW FLOW ALONG THE MISSOURI
RIVER VALLEY. AT THE SURFACE...MEAN SURFACE TROUGH EXTENDS ACROSS
NORTHERN COLORADO INTO CENTRAL NEBRASKA...WITH WEAK FLOW AND A
SECONDARY WEAK TROUGH AXIS/SURFACE CONVERGENT ZONE ALONG THE KS CO
BORDER EXTENDING SOUTH INTO SOUTH CENTRAL KS.
MODELS CONTINUE TO UNDERESTIMATE TDS WITH 60-70F TD VALUES REPORTED
MOST OF THE DAY...FINALLY BEGINNING TO FALL IN OUR NW. RESULT IS
MUCH HIGHER CAPE VALUES THAN PREVIOUSLY ADVERTISED WITH RAP ANALYSIS
SHOWS A SHARP GRADIENT OF SB CAPE FROM 250 J/KG IN NORTHEAST
COLORADO TO 3000 J/KG OVER OUR SOUTHERN CWA. CONSIDERING THE MOIST
BL LAYER AND FAVORABLE CAPE PROFILES OVER MOST OF THE AREA IT WON`T
TAKE MUCH FOR THUNDERSTORMS TO DEVELOP. WITH ONLY WEAK HEIGHT FALLS
THIS AFTERNOON/TONIGHT AND MODELS SHOWING ALMOST NO ACTIVITY
INITIATING OVER OUR CA (DESPITE LOW CINH)...I AM FAVORING ISOLATED
THUNDERSTORM MENTION FOR NOW. AS WITH LAST NIGHT...VERY LITTLE STORM
MOTION (0-6KM 0-5KT ACROSS MUCH OF THE AREA) WILL RESULT IN
POTENTIAL FOR FLASH FLOODING. IF CELL MERGERS OCCUR AND ARE ABLE TO
DEVELOP A COLD POOL OR OUTFLOW WE COULD SEE BETTER COVERAGE. LOW
CONFIDENCE AT THIS POINT.
SATURDAY...PATTERN WILL BE VERY SIMILAR AS TODAY WITH SEASONAL HIGHS
(UPPER 80S-MID 90S). GUIDANCE ACTUALLY INDICATING SUBSIDENCE WILL BE
IN PLACE...SO WHILE HIGH CAPE VALUES/DECENT MOISTURE PROFILES WILL
LIKELY SET UP OVER THE CWA ONCE AGAIN CONFIDENCE IN ANY INITIATION
IS EVEN LOWER THAN TODAY. I DECIDED TO KEEP THUNDERSTORM MENTION
OUT FOR NOW.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 200 PM MDT FRI JUL 31 2015
FOR THE EXTENDED PERIOD...THE LATTER PORTION OF THE WEEKEND RIGHT
THROUGH MUCH OF NEXT WEEK...THE ENTIRE TRI STATE REGION WILL SEE
ABOVE NORMAL TEMPERATURES BROUGHT ABOUT BY A STRONG AMPLIFIED
500/700 MB RIDGE OVER THE WESTERN PORTION OF THE COUNTRY...THAT
SHIFTS EASTWARD INTO THE PLAINS REGION BY NEXT WEDNESDAY. LATEST
MODEL RUNS STILL SHOW 850 MB TEMPS RANGING FROM +29C TO ALMOST
+35C...UNDER WNW UPPER FLOW. THIS IS GOING TO GIVE THE AREA DAYTIME
HIGHS WELL INTO THE 90S...WARMEST ON WEDNESDAY WHEN UPPER RIDGE AXIS
SETTLES OVER THE REGION AND COULD GIVE MID TO UPPER 90S TO THE AREA.
COOLER AIR COULD ARRIVE DURING THE DAY FRIDAY WITH SURFACE RIDGE
BUILDING SOUTH THRU THE PLAINS AFTER FRONTAL PASSAGE LATE THURSDAY
NIGHT.
DESPITE STRONG RIDGING OVER THE REGION OVER THE NEXT WEEK...SEVERAL
SHORTWAVES ARE EXPECTED TO TRAVERSE OVER THE NORTHERN HALF OF THE
RIDGE...BRINGING THE CHANCE FOR SHOWERS/THUNDERSTORMS. THIS ACTIVITY
THOUGH WILL SPARE THE FORECAST AREA FOR THIS UPCOMING WEEKEND...ONLY
TO BEGIN WITH A STRONG TROUGH LATE MONDAY INTO TUESDAY AND THEN
SUBSEQUENT SYSTEMS. BEST CHANCES FOR PRECIP THOUGH AS WEEK
PROGRESSES WILL BEGIN TO SHIFT MORE EASTWARD OVER THE CWA...DUE TO
MOVEMENT OF UPPER RIDGE WHICH WILL AFFECT PLACEMENT OF EACH LATTER
SHORTWAVE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 535 PM MDT FRI JUL 31 2015
VFR CONDITIONS ARE EXPECTED FOR BOTH TERMINALS FOR THE DURATION OF
THE TAF PERIOD.
A SMALL AREA OF CONVECTION NORTH/NORTHEAST OF THE GOODLAND AREA IS
PRODUCING AN AREA OF STORM OUTFLOW THAT WILL BRING GUSTY NORTH
WINDS TO KGLD FOR THE FIRST HOUR OF THE FORECAST. ONCE THE
BOUNDARY MOVES OVER THE TERMINAL...WINDS WILL RETURN TO THE
SOUTH/SOUTHWESTERLY DIRECTION OVERNIGHT. VARIABLE WINDS WILL BE
EXPERIENCED OVERNIGHT AT KMCK WITH GUSTY WINDS PICKING UP TOMORROW
AFTERNOON.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JN
AVIATION...MK
...UPDATE TO AVIATION FORECAST DISCUSSION...
.UPDATE...
ISSUED AT 551 PM CDT FRI JUL 31 2015
MADE VERY LITTLE CHANGE TO THE ONGOING FORECAST. WHILE
THUNDERSTORMS ARE ONGOING IN NEBRASKA WITH A STRONG SOUTHERLY
COMPONENT TO THE MOTION, INSTABILITY DECREASES SHARPLY WITH
APPROACH TOWARD THE KANSAS BORDER. THE MAIN INSTABILITY AXIS SEEMS
TO RUN FROM SOUTHEAST NEBRASKA INTO NORTHWEST MISSOURI SO COULD
SEE SOME THUNDERSTORM ACTIVITY CLIP NORTHERN AND PARTICULARLY
NORTHEAST PARTS OF THE FORECAST AREA THIS EVENING. THE HRRR IS
VERY AGGRESSIVE WITH THUNDERSTORM COVERAGE (AS IT CAN BE AT TIMES
OF WEAK FORCING) AND BELIEVE IT IS LIKELY OVERDONE WITH THE
OVERALL COVERAGE AND PERSISTENCE OF THE STORM ACTIVITY INTO
KANSAS. AT THE SAME TIME...A STRONG COLD POOL HAS DEVELOPED FROM
NORTHERN STORMS AND WILL LIKELY WEAKEN AS IT MOVES INTO NORTHERN
KS...POSSIBLY STRONG ENOUGH TO KICK OFF ANOTHER STORM OR TWO.
BOTTOM LINE...STORM CHANCES THIS EVENING REMAIN LOW AND FOCUSED
OVER NORTHERN AND PERHAPS NORTHEAST KANSAS. IF ANYTHING DEVELOPS
INTO THE AREA THERE IS A VERY SMALL CHANCE FOR IT TO PRODUCE
MARGINALLY SEVERE HAIL OR LOCALLY DAMAGING WINDS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 335 PM CDT FRI JUL 31 2015
THUNDERSTORMS WERE DEVELOPING IN THE MOISTURE AND INSTABILITY AXIS
ALONG AN OLD OUTFLOW BOUNDARY IN NORTHERN AND EASTERN NEBRASKA THIS
AFTERNOON AT 20Z. FORECAST SHEAR THIS EVENING ACROSS NORTHEAST
KANSAS IS MARGINAL IN THE 25 TO 30 KT RANGE WITH MLCAPE FORECAST IN
THE 1000-2000 J/KG RANGE. CONVECTION IN NEBRASKA IF IT HOLDS
TOGETHER WOULD TRACK SOUTHEAST INTO NORTHEAST KANSAS THIS EVENING.
WITH LACK OF UPPER FORCING AND THE FOCUS FOR INSTABILITY AND
MOISTURE NORTH IN NEBRASKA WILL KEEP SMALL CHANCES OF PRECIPITATION
ACROSS THE NORTHERN COUNTIES FOR THE EVENING HOURS. LOWS SHOULD FALL
INTO THE UPPER 60S TO LOW 70S.
SATURDAY...MODELS DEVELOP SCATTERED SHOWERS AND THUNDERSTORMS DURING
THE LATE AFTERNOON ACROSS NEBRASKA AND THEN SOUTHEAST INTO SOUTHWEST
IOWA, NORTHWEST MISSOURI AND FAR NORTHEAST KANSAS AHEAD OF A WEAK
SHORTWAVE TROUGH. WILL KEEP A SMALL CHANCE OF THUNDERSTORMS NEAR THE
NEBRASKA BORDER IN THE LATE AFTERNOON HOURS. HIGHS A LITTLE WARMER
IN THE LOW TO MID 90S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 335 PM CDT FRI JUL 31 2015
SATURDAY NIGHT T0 MONDAY...
ANOTHER WAVE IS FCST TO SLIDE SE ACROSS THE REGION SAT NIGHT WHICH
SHOULD BRING ANOTHER ROUND OF STORMS TO PARTS OF NE/IA/MO AND
PERHAPS CLIPPING FAR NORTHEAST KS WITHIN THE LOW LEVEL WAA REGIME.
STRONGEST FORCING SHOULD REMAIN NE OF THE AREA SO WILL ONLY KEEP
LOWER CHC POPS FOR SAT NIGHT. BY SUNDAY SFC LOW PRESSURE WILL SLIDE
INTO WI WITH A COLD FRONT FCST TO SAG INTO THE STATE BY PEAK
HEATING. WILL LEAVE SLIGHT CHCS IN THE FCST FOR THE NORTHERN HALF
NEAR THE FRONT ON SUNDAY FOR RISK OF ISOLATED THUNDER IN THE
EVENING. BETTER CHANCES FOR STORMS WOULD APPEAR TO ARRIVE BY MONDAY
NIGHT AND BEYOND AS MID/UPPER WAVES MOVE ACROSS THE ROCKIES INTO THE
PLAINS AND INTERACT WITH A FRONTAL BOUNDARY IN THE VICINITY.
MONDAY NIGHT TO FRIDAY...
UPPER LEVEL NORTHWEST FLOW CONTINUES AS A SHORTWAVE MOVES OVER
NORTHERN KANSAS MONDAY NIGHT TO TUESDAY MORNING. THIS SHORTWAVE IS
PROGGED TO EXIT THE AREA BY TUESDAY AFTERNOON, BEFORE ANOTHER CHANCE
FOR PRECIPITATION IS SEEN TUESDAY TO WEDNESDAY MORNING ASSOCIATED
WITH ANOTHER PASSING SHORTWAVE. WITH NORTHWEST FLOW CONTINUING
THROUGH THE END OF THE PERIOD, SLIGHT CHANCES FOR STORMS REMAIN
UNTIL FRIDAY. HIGHS REMAIN IN THE LOW TO MID 90S THROUGH THURSDAY,
WITH A SLIGHT COOL DOWN FRIDAY DUE TO A SURFACE FRONTAL PASSAGE.
LOWS STAY MILD IN THE UPPER 60S/LOW 70S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 618 PM CDT FRI JUL 31 2015
VFR CONDITIONS ARE LIKELY THROUGH THE TAF PERIOD. WINDS WILL VARY
AT TIMES BUT SHOULD BE MAINLY FROM THE SOUTH TO SOUTHEAST AND
LIGHT. STORMS TO THE NORTH ARE UNLIKELY TO REACH TAF SITES BUT
WILL MONITOR CLOSELY SHOULD THEY MOVE FARTHER SOUTH THAN
EXPECTED.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...53
LONG TERM...HELLER/OMITT
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
605 PM CDT FRI JUL 31 2015
...UPDATED AVIATION DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 1226 PM CDT FRI JUL 31 2015
THE SUMMER SUBTROPICAL RIDGE WAS CENTERED OVER ITS CLIMATOLOGICAL
POSITION FROM THE SOUTHERN ROCKIES INTO TEXAS TODAY. IN THE UPPER
TROPOSPHERE, WEST NORTHWEST FLOW EXTENDED FROM THE NORTHERN ROCKIES
THROUGH THE UPPER MISSISSIPPI VALLEY. WESTERN KANSAS WAS ON THE
SOUTH EDGE OF THE WESTERLIES AT 250MB. THE MESOSCALE CONVECTIVE
SYSTEM (MCS) THAT AFFECTED EXTREME SOUTHWEST KANSAS OVERNIGHT AND
THIS MORNING WAS DECREASING IN AREAL EXTENT AND MOVING VERY SLOWLY
TO THE EAST-SOUTHEAST...FOLLOWING ROUGHLY THE 3-8KM AGL MEAN FLOW
VECTOR (JUST NORTH OF THE CENTER OF THE MEAN ANTICYCLONE IN THIS
LAYER OVER WEST TEXAS). A COUPLE OF MESOSCALE CONVECTIVE VORTICITY
MAXIMAS COULD BE IDENTIFIED THROUGH VISIBLE SATELLITE AND EVEN THE
HOURLY RAP ANALYSIS FROM NEAR TUCUMCARI NEW MEXICO TO NEAR
SPRINGFIELD COLORADO. IT WOULD APPEAR AS OF THESE MESOSCALE FEATURES
WERE ACTUALLY HELPING TO MAINTAIN THE SMALL MCS THROUGH THE EARLY
AFTERNOON HOURS AS THE LEADING EDGE OF IT WAS MOVING INTO THE FAR
EASTERN OK-TX PANHANDLES. THE VERY NORTHERN EXTENT OF THIS MCS
EXTENDED INTO MORTON AND SEWARD COUNTIES, WHICH WAS HAVING AN IMPACT
ON SURFACE TEMPERATURES (COOLER THAN FORECAST IN THIS AREA). WE HAVE
ADJUSTED THE DAYTIME TEMPERATURES DOWNWARD ACROSS FAR SOUTHWEST
KANSAS AS A RESULT. ELSEWHERE...ESPECIALLY ACROSS WEST CENTRAL AND
CENTRAL KANSAS NORTH OF HIGHWAY 96, TEMPERATURES SHOULD TOP OUT IN
THE LOWER TO MID 90S.
AS WE GO IN TO TONIGHT...ANOTHER SMALL MCS SHOULD EVOLVE THROUGH THE
LATE NIGHT HOURS FROM CONVECTION ACROSS THE HIGHER TERRAIN OF THE
RATON MESA REGION. THIS CONVECTION SHOULD FOLLOW THE SAME GENERAL
TRACK AS THIS MORNINGS MCS, SO WE WILL KEEP THE BEST POPS ACROSS FAR
SOUTHWEST KANSAS AGAIN IN THE 40-50 PERCENT RANGE. THE BULK OF LATE
TONIGHT/TOMORROWS MCS SHOULD REMAIN ACROSS THE PANHANDLES REGION. IT
SHOULD BE CLOSE TO A RINSE AND REPEAT TYPE OF DEAL TOMORROW WITH A
SLOWLY DECAYING MCS SOMEWHERE JUST SOUTH OF OUR FORECAST AREA (OR
PERHAPS CLIPPING MORTON-SEWARD-MEADE) WITH WARMEST TEMPERATURES UP
NORTH ALONG I-70 (MID 90S) AND COOLEST TEMPERATURES ALONG THE OK
BORDER (LOWER-MID 80S, IF EVEN THAT WARM).
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 338 PM CDT FRI JUL 31 2015
THE BEST CHANCE FOR THE NEXT ORGANIZED PRECIPITATION EVENT WILL BE
MONDAY NIGHT INTO TUESDAY. THE GLOBAL SPECTRAL MODELS CONTINUE TO
SHOW AN INTERACTION BETWEEN MONSOON PERTURBATIONS MOVING NORTHWARD
THROUGH THE DESERT SOUTHWEST...AND AN INCOMING SUBTROPICAL PACIFIC
JET MOVING INTO THE INTERMOUNTAIN WEST REGION. THIS WILL ACT TO
SHIFT THE MONSOON CIRCULATION NORTHEASTWARD SOME...ENHANCING THE
PRECIPITATION POTENTIAL FOR SOUTHWEST KANSAS. IT VERY WELL COULD BE
JUST ONE BIG MCS WE SEE OUT OF THIS EVENT, IN WHICH CASE IF THE
ECMWF HAS A HANDLE ON THINGS, WOULD BE MONDAY NIGHT. THIS IS WHEN
THE HIGHEST POPS ARE IN THE GRIDS FOR THE ENTIRE REGION. ONCE THAT
WAVE EXITS THE CENTRAL PLAINS...THE SUMMER SUBTROPICAL RIDGE WILL
BUILD BACK IN, HOWEVER DEEP TROPOSPHERIC MONSOON MOISTURE WILL BE
FAIRLY SCANT AND IT WILL NEED TO BE RECHARGED AGAIN BY WAY OF LATE
DAY HIGH TERRAIN THUNDERSTORMS. THE LATEST ECMWF FAVORS RIDGE-
BUILDING INTO THE NORTHERN PLAINS WHICH WOULD RESULT IN A WARMING OF
THE LOWER TROPOSPHERE AND SURFACE TEMPERATURES REACHING OR EXCEEDING
THE UPPER 90S BY MID TO LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 604 PM CDT FRI JUL 31 2015
18Z BUFR SOUNDINGS INDICATING MOISTURE WILL INCREASE IN THE 850MB
TO 750 MB LEVELS EARLY SATURDAY MORNING AS A WEAK UPPER LEVEL
DISTURBANCE CROSSES SOUTHWEST KANSAS. THIS WILL BRING A PERIOD OF
4000FT TO 8000FT CEILINGS TO PORTIONS OF WESTERN KANSAS AFTER 09Z
SATURDAY. WINDS WILL BE SOUTHERLY AT LESS THAN 10 KNOTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 68 87 67 93 / 10 10 10 10
GCK 67 87 67 92 / 10 10 10 10
EHA 66 85 67 92 / 30 40 20 10
LBL 68 83 68 92 / 20 30 20 10
HYS 67 93 67 95 / 10 10 10 10
P28 71 90 70 94 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...UMSCHEID
AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
436 PM MDT THU JUL 30 2015
.UPDATE...
ISSUED AT 430 PM MDT THU JUL 30 2015
ISSUED A QUICK UPDATE TO ADJUST COVERAGE AND THUNDERSTORM TIMING
MOVING INTO THE EASTERN COLORADO COUNTIES. THE WRF MODELS SEEM TO
BE HAVING THE BEST HANDLE ON THE CURRENT CONVECTIVE MODE...HOWEVER
PRECIPITATION IN THE MODELS ARE 3-6 HOURS LATE IN DEVELOPMENT.
STORMS MAY DISSIPATE EARLIER THAN ANTICIPATED DUE TO THE EARLIER
DEVELOPMENT...BUT WILL LEAVE IN PRECIPITATION CHANCES AFTER
MIDNIGHT MDT FOR NOW.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 200 PM MDT THU JUL 30 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD RIDGE
ACROSS THE SOUTHERN PLAINS EXTENDING ACROSS THE CENTRAL ROCKIES AND
ACROSS THE GREAT BASIN. NW FLOW IS IN PLACE ACROSS THE NORTHERN
PLAINS AND GREAT LAKES REGIONS. A WEAK RIPPLE IN THE HEIGHT FIELD IS
DEPICTED OVER NW KANSAS WITH A STRONGER PV HEIGHT ANOMALY OVER NEW
MEXICO AND STRONGER SIGNAL IN WV IMAGERY. AT THE SURFACE LOW
PRESSURE HAS DEVELOPED ACROSS EASTERN COLORADO WITH A STATIONARY
FRONT EXTENDING FROM THE SW TO NE TOWARDS THE NEBRASKA PANHANDLE.
HIGH PRESSURE IS IN PLACE ACROSS THE CENTRAL PLAINS AND CENTRAL
MISSISSIPPI RIVER VALLEY.
THIS AFTERNOON-TONIGHT...CAPE VALUES IN THE 1500-2500 J/KG RANGE ARE
CURRENTLY IN PLACE WITH HIGHER TD VALUES (UPPER 50S TO MID 60S).
RAP/HRRR INDICATE CAP ALREADY WEAKENED...AND THUNDERSTORM ACTIVITY
MAY BEGIN TO DEVELOP ALONG WEAK CONVERGENCE ZONE NEAR SURFACE
TROUGH/STATIONARY FRONT IN EASTERN COLORADO. GUIDANCE GENERALLY
SHOWS BETTER PRECIP SIGNAL IN THIS AREA. VERY WEAK LIFT IS IN PLACE
AND AT THIS POINT COVERAGE LOOKS TO BE ISOLATED TO WIDELY SCATTERED
THROUGH TONIGHT. THERE WILL BE SOME WAA THROUGH THE NIGHT WHICH
COULD SUPPORT CONTINUED DEVELOPMENT...HOWEVER WITH BEST FORCING
OUTSIDE OUR CWA...NOT A LOT OF CONFIDENCE. I LIMITED POPS TO 15-24
RANGE (SLIGHT CHANCE). WITH WEAK SHEER PROFILES IN PLACE...LIMITED
FORCING...AND MID LEVEL LAPSE RATES MAINLY LESS THAN 7 C/KM
THUNDERSTORM ACTIVITY IS NOT EXPECTED TO BECOME ORGANIZED.
FRIDAY...SURFACE TROUGH SHIFTS EAST TO BE CENTERED ROUGHLY OVER OUR
CWA AND MAY ACT AS A FOCUS/INITIATION POINT FOR AFTERNOON
THUNDERSTORM ACTIVITY. BEST UPPER LEVEL SUPPORT IS IN THE MORNING
OUTSIDE OUR CWA...WITH POSSIBLY LESS UPPER LEVEL SUPPORT FRIDAY
AFTERNOON THAN TODAY. THERE SHOULD STILL BE ENOUGH
INSTABILITY/MOISTURE IN PLACE TO SUPPORT SOME THUNDERSTORM ACTIVITY
ALONG TROUGH AXIS...HOWEVER COVERAGE STILL APPEARS TO BE ISOLATED IN
NATURE. EFFECTIVE SHEER PROFILES AROUND 30KT AND CAPE VALUES 1500-
3000 J/KG COULD SUPPORT A FEW STRONGER STORMS HOWEVER LIKE TODAY
SEVERE THREAT APPEARS TO BE LOW. HIGH TEMPERATURES WILL BE SLIGHTLY
WARMER AND STILL SEASONAL WITH VALUES RANGING FROM THE UPPER 80S TO
LOWER 90S. A FEW MID 90 TEMPERATURES WILL BE POSSIBLE AT KMCK/KHLC.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 150 PM MDT THU JUL 30 2015
ABOVE NORMAL TEMPERATURES ARE ON TAP FOR THE ENTIRE TRI STATE
REGION...AS MAIN WEATHER FOCUS FOR THE EXTENDED PERIOD WILL CONCERN
AMPLIFIED H5/H7 RIDGE OVER THE WESTERN PORTION OF THE COUNTRY...
SHIFTING EASTWARD INTO THE PLAINS REGION BY NEXT WEDNESDAY/THURSDAY.
EXPECTING BROAD WNW DOWNSLOPE FLOW AT 700/500 MB WITH RIDGE TO OUR
WEST...WITH RIDGE AXIS OVER THE PLAINS BY MIDWEEK NEXT WEEK. 850 MB
TEMPS DO RANGE FROM +28C UP TO +33C DURING THIS TIME...WITH WARMEST
SET TO OCCUR WED/THURS...COINCIDING WITH RIDGE AXIS SETTING UP OVER
THE AREA. WITH THESE CONDITIONS...DAYTIME HIGH TEMPERATURES WILL
RANGE IN THE LOWER TO MID 90S...AND OVERNIGHT LOWS IN THE LOW TO MID
60S.
THE AREA WILL ALSO SEE THE CHANCES FOR SHOWERS AND THUNDERSTORMS
DESPITE THE INCREASE TEMPS. SEVERAL SHORTWAVES MOVING DOWN ALONG THE
EAST SIDE OF THE MID-LEVEL RIDGE FRIDAY/FRIDAY NIGHT...NEXT MONDAY
INTO TUESDAY...AND AGAIN LATE WEDNESDAY INTO THURSDAY WHEN SURFACE
FRONT IS FOLLOWED BY TRAILING SHORTWAVE. CURRENT GFS A BIT MORE IN-
LINE WITH LATEST ECMWF...MAKING CONFIDENCE A BIT STRONGER IN KEEPING
CHANCE POPS FOR LATTER PORTION OF THE FORECAST. THE PUSH OF THE
UPPER RIDGE EASTWARD INTO THE PLAINS DOES PUT A BIT MORE EMPHASIS
FOR HIGHER POP CHANCES OVER EASTERN ZONES ON WEDNESDAY INTO
THURSDAY. AS WITH EXPECTED RAINFALL POTENTIAL...THE CLOUD COVER WITH
THESE EVENTS COULD IMPACT DAYTIME HIGHS/OVERNIGHT LOWS...ESPECIALLY
IN EASTERN ZONES AS WEEK PROGRESSES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1124 AM MDT THU JUL 30 2015
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AT BOTH KGLD
AND KMCK TERMINALS. PRIMARY AVIATION CONCERN WILL BE POTENTIAL FOR
THUNDERSTORMS AT BOTH TERMINALS THIS AFTERNOON AND EVENING. AT
THIS TIME IT APPEARS COVERAGE WILL BE ISOLATED WITH LIMITED
INSTABILITY AND FORCING. CONFIDENCE IS TOO LOW TO INCLUDE MENTION
AT EITHER TERMINAL...SO WILL NEED TO MONITOR.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...MK
SHORT TERM...DR
LONG TERM...JN
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
200 PM MDT THU JUL 30 2015
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 200 PM MDT THU JUL 30 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD RIDGE
ACROSS THE SOUTHERN PLAINS EXTENDING ACROSS THE CENTRAL ROCKIES AND
ACROSS THE GREAT BASIN. NW FLOW IS IN PLACE ACROSS THE NORTHERN
PLAINS AND GREAT LAKES REGIONS. A WEAK RIPPLE IN THE HEIGHT FIELD IS
DEPICTED OVER NW KANSAS WITH A STRONGER PV HEIGHT ANOMALY OVER NEW
MEXICO AND STRONGER SIGNAL IN WV IMAGERY. AT THE SURFACE LOW
PRESSURE HAS DEVELOPED ACROSS EASTERN COLORADO WITH A STATIONARY
FRONT EXTENDING FROM THE SW TO NE TOWARDS THE NEBRASKA PANHANDLE.
HIGH PRESSURE IS IN PLACE ACROSS THE CENTRAL PLAINS AND CENTRAL
MISSISSIPPI RIVER VALLEY.
THIS AFTERNOON-TONIGHT...CAPE VALUES IN THE 1500-2500 J/KG RANGE ARE
CURRENTLY IN PLACE WITH HIGHER TD VALUES (UPPER 50S TO MID 60S).
RAP/HRRR INDICATE CAP ALREADY WEAKENED...AND THUNDERSTORM ACTIVITY
MAY BEGIN TO DEVELOP ALONG WEAK CONVERGENCE ZONE NEAR SURFACE
TROUGH/STATIONARY FRONT IN EASTERN COLORADO. GUIDANCE GENERALLY
SHOWS BETTER PRECIP SIGNAL IN THIS AREA. VERY WEAK LIFT IS IN PLACE
AND AT THIS POINT COVERAGE LOOKS TO BE ISOLATED TO WIDELY SCATTERED
THROUGH TONIGHT. THERE WILL BE SOME WAA THROUGH THE NIGHT WHICH
COULD SUPPORT CONTINUED DEVELOPMENT...HOWEVER WITH BEST FORCING
OUTSIDE OUR CWA...NOT A LOT OF CONFIDENCE. I LIMITED POPS TO 15-24
RANGE (SLIGHT CHANCE). WITH WEAK SHEER PROFILES IN PLACE...LIMITED
FORCING...AND MID LEVEL LAPSE RATES MAINLY LESS THAN 7 C/KM
THUNDERSTORM ACTIVITY IS NOT EXPECTED TO BECOME ORGANIZED.
FRIDAY...SURFACE TROUGH SHIFTS EAST TO BE CENTERED ROUGHLY OVER OUR
CWA AND MAY ACT AS A FOCUS/INITIATION POINT FOR AFTERNOON
THUNDERSTORM ACTIVITY. BEST UPPER LEVEL SUPPORT IS IN THE MORNING
OUTSIDE OUR CWA...WITH POSSIBLY LESS UPPER LEVEL SUPPORT FRIDAY
AFTERNOON THAN TODAY. THERE SHOULD STILL BE ENOUGH
INSTABILITY/MOISTURE IN PLACE TO SUPPORT SOME THUNDERSTORM ACTIVITY
ALONG TROUGH AXIS...HOWEVER COVERAGE STILL APPEARS TO BE ISOLATED IN
NATURE. EFFECTIVE SHEER PROFILES AROUND 30KT AND CAPE VALUES 1500-
3000 J/KG COULD SUPPORT A FEW STRONGER STORMS HOWEVER LIKE TODAY
SEVERE THREAT APPEARS TO BE LOW. HIGH TEMPERATURES WILL BE SLIGHTLY
WARMER AND STILL SEASONAL WITH VALUES RANGING FROM THE UPPER 80S TO
LOWER 90S. A FEW MID 90 TEMPERATURES WILL BE POSSIBLE AT KMCK/KHLC.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 150 PM MDT THU JUL 30 2015
ABOVE NORMAL TEMPERATURES ARE ON TAP FOR THE ENTIRE TRI STATE
REGION...AS MAIN WEATHER FOCUS FOR THE EXTENDED PERIOD WILL CONCERN
AMPLIFIED H5/H7 RIDGE OVER THE WESTERN PORTION OF THE COUNTRY...
SHIFTING EASTWARD INTO THE PLAINS REGION BY NEXT WEDNESDAY/THURSDAY.
EXPECTING BROAD WNW DOWNSLOPE FLOW AT 700/500 MB WITH RIDGE TO OUR
WEST...WITH RIDGE AXIS OVER THE PLAINS BY MIDWEEK NEXT WEEK. 850 MB
TEMPS DO RANGE FROM +28C UP TO +33C DURING THIS TIME...WITH WARMEST
SET TO OCCUR WED/THURS...COINCIDING WITH RIDGE AXIS SETTING UP OVER
THE AREA. WITH THESE CONDITIONS...DAYTIME HIGH TEMPERATURES WILL
RANGE IN THE LOWER TO MID 90S...AND OVERNIGHT LOWS IN THE LOW TO MID
60S.
THE AREA WILL ALSO SEE THE CHANCES FOR SHOWERS AND THUNDERSTORMS
DESPITE THE INCREASE TEMPS. SEVERAL SHORTWAVES MOVING DOWN ALONG THE
EAST SIDE OF THE MID-LEVEL RIDGE FRIDAY/FRIDAY NIGHT...NEXT MONDAY
INTO TUESDAY...AND AGAIN LATE WEDNESDAY INTO THURSDAY WHEN SURFACE
FRONT IS FOLLOWED BY TRAILING SHORTWAVE. CURRENT GFS A BIT MORE IN-
LINE WITH LATEST ECMWF...MAKING CONFIDENCE A BIT STRONGER IN KEEPING
CHANCE POPS FOR LATTER PORTION OF THE FORECAST. THE PUSH OF THE
UPPER RIDGE EASTWARD INTO THE PLAINS DOES PUT A BIT MORE EMPHASIS
FOR HIGHER POP CHANCES OVER EASTERN ZONES ON WEDNESDAY INTO
THURSDAY. AS WITH EXPECTED RAINFALL POTENTIAL...THE CLOUD COVER WITH
THESE EVENTS COULD IMPACT DAYTIME HIGHS/OVERNIGHT LOWS...ESPECIALLY
IN EASTERN ZONES AS WEEK PROGRESSES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1124 AM MDT THU JUL 30 2015
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD AT BOTH KGLD
AND KMCK TERMINALS. PRIMARY AVIATION CONCERN WILL BE POTENTIAL FOR
THUNDERSTORMS AT BOTH TERMINALS THIS AFTERNOON AND EVENING. AT
THIS TIME IT APPEARS COVERAGE WILL BE ISOLATED WITH LIMITED
INSTABILITY AND FORCING. CONFIDENCE IS TOO LOW TO INCLUDE MENTION
AT EITHER TERMINAL...SO WILL NEED TO MONITOR.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JN
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1129 PM MDT WED JUL 29 2015
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 221 PM MDT WED JUL 29 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS WEST-
NORTHWEST FLOW ACROSS NORTHERN PLAINS WITH BROAD RIDGE ACROSS THE
SOUTHERN US AND TROUGH ACROSS THE NORTHERN GREAT LAKES. AT THE
SURFACE HIGH PRESSURE EXTEND FROM THE NORTHERN PLAINS ACROSS
WESTERLY KANSAS.
THIS AFTERNOON-TONIGHT...AXIS OF FAVORABLE LAPSE RATES (AROUND
7C/KM) IS IN THE PROCESS OF SHIFTING EAST WITH WEAK SHORTWAVE
TROUGH. AS THIS SHIFTS EAST CHANCE FOR SPRINKLES/LIGHT SHOWERS
COMES TO AN END (BY EARLY EVENING). LOW TEMPS TONIGHT WILL BE VERY
SIMILAR TO LAST NIGHT WITH NEAR SEASONAL VALUES AROUND 60F...AND
SOME COOLER LOCATIONS IN THE MID-UPPER 50S.
THURSDAY...H5 RIDGE BEINGS TO AMPLIFY ACROSS WESTERN US RESULTING
IN STRENGTHENING OF LEE TROUGH AND INCREASE IN WAA ACROSS EASTERN
COLORADO/FAR WESTERN KANSAS. TEMPS WILL APPROACH SEASONAL VALUES
IN THE UPPER 80S/NEAR 90 FOR MOST PARTS OF OUR CWA. STEEP MID
LEVEL LAPSE RATES AND 400-700 J/KG CAPE AXIS BEGINS TO BUILD BACK
OVER THE WESTER CWA...WHICH COULD RESULT IN THUNDERSTORM
DEVELOPMENT POSSIBLY AS EARLY AS MID MORNING THURSDAY. BEST
SURFACE CONVERGENCE IS WEST OF CWA...SO UNTIL WEAK ENERGY TOWARDS
THE CWA FROM THE SW DURING THE AFTERNOON WE PROBABLY WONT SEE ANY
ACTIVITY. BEST LIFT IS ALSO SOUTH OF OUR CWA...SO CONFIDENCE IS
LOW ON COVERAGE AT THIS POINT. BEST SIGNAL/CHANCES WILL BE ACROSS
THE WEST ROUGHLY ALONG KS/CO STATE LINE. WITH WEAK CAPE VALUES
SEVERE POTENTIAL IS VERY LOW DESPITE INCREASING EFFECTIVE SHEER
LATE THURSDAY AFTERNOON.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 145 PM MDT WED JUL 29 2015
THE LONG TERM FORECAST PERIOD WILL BE DOMINATED BY AN UPPER LEVEL
HIGH PRESSURE SYSTEM POSITIONED OVER THE SOUTH CENTRAL CONUS...WHICH
WILL BRING THE RETURN OF NEAR NORMAL TEMPERATURES IN THE LOWER TO
MID 90S ON FRIDAY. THE UPPER LEVEL RIDGE WILL CONTINUE TO AMPLIFY
OVER THE WESTERN THIRD OF THE CONUS ON FRIDAY...WHICH WILL BRING
MOSTLY DRY CONDITIONS. HOWEVER...A FRONTAL BOUNDARY WILL BE
POSITIONED OVER THE SOUTH/SOUTHWEST CORNER OF THE FORECAST AREA
WHICH WILL BRING SOME CHANCES FOR SOME DEVELOPING SHOWERS AND
THUNDERSTORMS FOR FRIDAY THROUGH SATURDAY. SEVERE INDICATORS AT
THIS TIME LOOK MARGINAL AT BEST...SO SEVERE WEATHER IS NOT
ANTICIPATED AT THIS TIME.
AS UPPER LEVEL RIDGE AMPLIFIES OVER THE WEEKEND WITH A LACK OF A
SURFACE FORCING MECHANISM...SO EXPECTING DRY WEATHER FOR THE REST OF
THE WEEKEND SATURDAY NIGHT THROUGH SUNDAY. WARM SURFACE SOUTHERLY
FLOW WILL CONTINUE TO BRING INCREASED MOISTURE WITH DEW POINTS IN
THE MID 60S AND TEMPERATURES IN THE UPPER 80S TO LOWER 90S.
THE NEXT CHANCES FOR PRECIPITATION WILL BE TUESDAY AS AN UPPER LEVEL
SHORTWAVE TROUGH APPROACHES THE CENTRAL HIGH PLAINS REGION. MODEL
FORECASTS DIFFER AS TO THE LOCATION AND TIMING OF THE FEATURE...WITH
THE ECMWF BRINGING THE DISTURBANCE IN THE FASTEST STARTING TUESDAY.
AT THIS POINT...NOT VERY CONFIDENT THAT SHOWERS AND STORMS WILL
DEVELOP CONSIDERING GFS/CANADIAN/DGEX MODELS ALL INDICATE THE RIDGE
MAINTAINING STRENGTH OVER THE REGION. TO STAY WITHIN FORECAST
COLLABORATION THRESHOLDS...KEPT CHANCES FOR PRECIPITATION IN THE
FORECAST...ESPECIALLY CONSIDERING THAT THE ECMWF TENDS TO LATCH ON
TO FORECAST PATTERNS SOONER THAN THE OTHER MODELS IN THE LONG TERM
PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1127 PM MDT WED JUL 29 2015
VFR CONDITIONS EXPECTED FOR THE 6Z TAFS. LIGHT WINDS WILL CONTINUE
THROUGH THE TAF PERIOD. SOUTHERLY WINDS TONIGHT WILL GRADUALLY
TURN TO THE SOUTHEAST DURING THE AFTERNOON.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...MK
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS JACKSON KY
243 AM EDT THU JUL 30 2015
.UPDATE...
ISSUED AT 243 AM EDT THU JUL 30 2015
COLD FRONT WAS POSITIONED FROM NEAR KBNA TO NEAR KDAY. CONVECTION
HAS ALMOST DIED OUT OVER THE LOCAL AREA...BUT CAN NOT RULE OUT
SOMETHING POPPING UP YET AHEAD OF THE FRONT. HAVE LOWERED POPS TO
20 PERCENT...AND THEN DROPPING BELOW THE THRESHOLD FOR THE MENTION
OF PRECIP AFTER THE FRONT PASSES SOUTHEAST IN THE MORNING.
UPDATE ISSUED AT 1020 PM EDT WED JUL 29 2015
THE COLD POOL ASSOCIATED WITH THE LINE OF STORMS HAS CONTINUED TO
CONSOLIDATE TO THE WEST AND SOUTH OF OUR AREA. ONLY A FEW OF OUR
SOUTHWEST COUNTIES WILL SEE LIKELY RAINS OVER THE NEXT HOUR OR SO.
THE REMNANT STRATIFORM RAINFALL ACROSS CENTRAL KENTUCKY IS NOT
MOVING MUCH...AND WILL GRADUALLY WEAKEN...MAINLY IN PLACE. THE
LAST FEW RUNS OF THE HRRR HAS GENERALLY CAUGHT ON TO THE ONGOING
CONVECTIVE TRENDS. AS SUCH...IT APPEARS THAT THERE MAY NOT BE MUCH
IN THE WAY OF ACTIVITY UNTIL THE ACTUAL FRONTAL BOUNDARY MOVES
SOUTHEAST ACROSS THE AREA DEEPER INTO THE OVERNIGHT HOURS...WHEN A
SLIGHT UPTICK IN ACTIVITY MAY OCCUR. WILL THEREFORE HANG ONTO
SLIGHT TO CHANCE POPS. ALSO ADJUSTED THE LOWS UP A TOUCH...AS THE
PUSH BEHIND THE FRONT IS NOT VERY STRONG. THE BEST CHANCE OF
SEEING SOME UPPER 60 DEGREE READINGS LOOKS TO BE ALONG AND NORTH
OF I-64. UPDATES HAVE BEEN SENT.
UPDATE ISSUED AT 813 PM EDT WED JUL 29 2015
THE LATEST RADAR MOSAIC SHOWS A CONVECTIVE LINE ACROSS CENTRAL
AND WESTERN KENTUCKY. NEW CELLS HAD BEEN MORE LIVELY A BIT FURTHER
NORTHEAST EARLIER...BUT SOME PRECURSORY STORMS TAPPED INTO THE
BETTER AVAILABLE AIR MASS...AND NOW THERE IS GENERALLY A WEAKENING
TREND ON THE EASTERN FLANK OF THE LINE...WITH BETTER COLD POOL AND
ASSOCIATED NEW DEVELOPMENT ALIGNING MORE TOWARDS THE SOUTH...WHERE
BETTER INSTABILITY REMAINS. STILL...THINK THAT SOME DEBRIS CELLS
WILL MAKE IT INTO THE WEST IN THE NEXT 1 TO 2 HOURS...AND HAVE
UPPED THE POPS TO HIGH CHANCE TO LIKELY FOR THOSE LOCATIONS. AS WE
LOSE HEATING...EXPECT AN OVERALL GRADUAL DIMINISHMENT...HOWEVER
WILL STILL HAVE TO KEEP AN EYE ON HEAVY RAINERS...GIVEN THE HIGH
PWATS AND THE POTENTIAL FOR TRAINING.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 343 PM EDT WED JUL 29 2015
AS OF MID AFTERNOON A MID LEVEL RIDGE WAS CENTERED OVER THE
SOUTHERN PLAINS REGION...WITH A CLOSED MID LEVEL LOW OVER
NORTHWESTERN ONTARIO AND THE ASSOCIATED TROUGH SOUTH INTO THE MS
VALLEY REGION. AT THE SFC...AN AREA OF LOW PRESSURE WAS CENTERED
OVER ONTARIO WITH A COLD FRONT SOUTH INTO THE CENTRAL GREAT LAKES
AND THEN SOUTHWEST INTO THE MID MS VALLEY AND CENTRAL PLAINS.
CONVECTION HAS DEVELOPED ALONG OR IN ADVANCE OF THIS FRONT OVER OH
AND IN SOUTHWEST INTO WESTERN KY. ADDITIONAL CONVECTION HAS
DEVELOPED NEAR A MOISTURE GRADIENT EVIDENT IN PW FROM NORTHERN KY
SOUTH INTO CENTRAL KY. THIS CONVECTION HAS BEEN GENERALLY SLOW
MOVING WITH HEAVY RAINFALL RATES. AREA WIDE...A WARM AND MOIST
AIR MASS IS IN PLACE WITH TEMPERATURES IN THE MID TO UPPER 80S TO
NEAR 90 AND DEW POINTS IN THE UPPER 60S TO MID 70S.
THE CLOSED MID LEVEL LOW WILL TRACK TO HUDSON BAY WITH THE
TRAILING SHORTWAVE TROUGH MOVING THROUGH THE GREAT LAKES AND MID
AND UPPER OH VALLEY REGION TONIGHT. THIS SHORTWAVE TROUGH WILL
MOVE INTO THE NORTHEASTERN CONUS THROUGH THURSDAY. AT THE SAME
TIME...THE MID LEVEL RIDGE WILL RETROGRADE AND AMPLIFY AND BECOME
CENTERED OVER THE SOUTHERN ROCKIES OR FOUR CORNERS REGION. THIS
WILL PUT THE REGION IN NW FLOW ALOFT LATE IN THE PERIOD. AT THE
SFC...THE COLD FRONT WILL CROSS THE REGION BY LATE TONIGHT OR
EARLY ON THURSDAY. THEN...HIGH PRESSURE WILL BUILD IN BEHIND THE
DEPARTING COLD FRONT AND USHER IN SLIGHTLY COLDER...BUT MORE
NOTICEABLY DRIER AIR INTO THE REGION.
RATHER MEAGER MID LEVEL FORCING AND NON OPTIMAL TIMING OF THE
FROPA DURING THE LATE EVENING INTO OVERNIGHT HOURS SHOULD LIMIT
CONVECTION THIS EVENING AND TONIGHT TO ISOLATED TO SCATTERED
COVERAGE. IT STILL APPEARS THAT THERE SHOULD BE A PEAK IN COVERAGE
OVER THE NEXT 3 HOURS OR SO...AND THEN MORE ORGANIZED CONVECTION
WITH A POSSIBLE BROKEN LINE OR LINE SEGMENTS OF SHOWERS AND
THUNDERSTORMS AS THE COLD FRONT MOVES THROUGH. WITH RELATIVELY
SLOW STORM MOTIONS EXPECTED DUE TO WEAK FLOW ALOFT AND A MOIST
AIR MASS IN PLACE...ANY STRONGER THUNDERSTORMS COULD PRODUCE VERY
HEAVY RAINFALL RATES AND OUTFLOW WIND GUSTS IN EXCESS OF 30 MPH
WILL BE POSSIBLE THIS EVENING SIMILAR TO A GUST OBSERVED OVER
CENTRAL KY EARLIER THIS AFTERNOON.
A SHOWER OR POSSIBLY A THUNDERSTORM COULD LINGER EARLY ON
THU...OVER THE SOUTHEASTERN CWA...PARTICULARLY NEAR THE VA BORDER.
OTHERWISE... AS DRIER AIR MOVES IN THROUGHOUT THE COLUMN SKIES
SHOULD BECOME MOSTLY SUNNY IN MOST LOCATIONS ON THU AFTERNOON.
WITH THE HIGH BUILDING IN...CLEAR SKIES AND LIGHT WINDS SHOULD SET
THE STAGE FOR VALLEY FOG FORMATION LATE IN THE PERIOD. ENOUGH
DRIER AIR SHOULD WORK IN FOR SOME OF THE NORMALLY COLDER LOCATIONS
ALONG...OR NORTH OF THE MTN PARKWAY COULD TOUCH THE UPPER 50S.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 256 PM EDT WED JUL 29 2015
THE EXTENDED PERIOD LOOKS FAIRLY BENIGN AS SURFACE HIGH PRESSURE
TAKES CONTROL OF THE REGION THROUGH EARLY NEXT WEEK. THIS WILL
ALLOW FOR SLIGHTLY COOLER AND DRIER AIR TO FILTER INTO THE REGION
FOR THE WEEKEND. HIGHS FRIDAY THROUGH SUNDAY WILL BE IN THE LOW TO
MID 80S...BUT DEW POINTS IN THE UPPER 50S AND LOW 60S WILL MAKE
THOSE READINGS FEEL MUCH MORE PLEASANT THAN THEY HAVE RECENTLY.
A WEAK AND MOISTURE STARVED FRONT APPROACHES THE REGION SATURDAY
MORNING...WITH BOTH THE GFS AND ECMWF SHOWING THE PRECIP FALLING
APART BEFORE IT REACHES THE FORECAST AREA. THIS IS LIKELY DUE TO
THE DRY AIR/RIDGING AT THE SURFACE. THERE IS SOME MID LEVEL
MOISTURE AND WEAK ENERGY WITH THE FRONT AS IT PASSES TO OUR NORTH
SO HAVE KEPT A SLIGHT CHANCE OF AN ISOLATED SHOWER IN THE FAR
NORTHERN COUNTIES. BUT DO NOT EXPECT MUCH MORE THAN AN INCREASE IN
SOME MID LEVEL CLOUDS ON SATURDAY FOR MOST AREAS.
SHOWER CHANCES RETURN TO THE REGION BY TUESDAY AS THE UPPER LEVEL
PATTERN BECOMES MORE ACTIVE. MODELS INDICATE THAT SEVERAL UPPER
LEVEL IMPULSES EMBEDDED IN THE NW FLOW WILL MOVE ACROSS EASTERN
KENTUCKY THROUGH THE END OF THE FORECAST PERIOD BRINGING INCREASED
SHOWER AND THUNDERSTORM CHANCES THROUGH THE END OF THE WORK WEEK.
TEMPERATURES (AND HUMIDITY) WILL INCREASE BACK INTO THE UPPER 80S
BY THE END OF THE PERIOD...WITH HEAT INDICES LIKELY SURPASSING THE
90 DEGREE MARK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 243 AM EDT THU JUL 30 2015
CONDITIONS WERE MOSTLY VFR AT THE START OF THE PERIOD. A
DETERIORATION TO IFR AND MVFR IS EXPECTED OVERNIGHT. IMPROVEMENT
BACK TO VFR SHOULD OCCUR ON THURSDAY MORNING. A SHOWER OR
THUNDERSTORM WILL BE POSSIBLE UP UNTIL A COLD FRONT MOVES THROUGH
FROM NW TO SE. THIS WILL HAPPEN BETWEEN ABOUT 09Z AND 16Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...HAL
SHORT TERM...JP
LONG TERM...JVM
AVIATION...HAL
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1140 PM CDT WED JUL 29 2015
.AVIATION...HRRR HAS LATE EVENING CONVECTION NEAR THE COAST AROUND
CAMERON AND THIS IS CONFIRMED BY THE CURRENT RADAR. HRRR TAKES
CONVECTION IN THE ATCHAFALAYA BASIN AND MOVES IT INTO THE ACADIANA
AIRPORTS LFT AND ARA SO ADDED VCTS FOR THE NEXT FEW HOURS. LATER
TNITE THIS ACTIVITY MOVES INTO THE LCH AREA. AFTER THE ATMOSPHERE
SETTLES IN THE MORNING, CONVECTION REGENERATES WITH AFTERNOON
HEATING SO ADDED VCTS AGAIN FOR THE TERMINALS. UPPER LEVEL
DIFLUENCE IS ACTING ON CONVECTION TNITE AND ADDITIONAL MID LEVEL MOISTURE
IS INDICATED ON THURSDAY.
SWEENEY
&&
.PREV DISCUSSION... /ISSUED 1010 PM CDT WED JUL 29 2015/
DISCUSSION...
REGIONAL 88DS SHOW A FAIR AMOUNT OF CONVECTION ONGOING MAINLY OVER
SERN LA...ALTHOUGH IT DOES SPILL OVER INTO LOWER ACADIANA/CAMERON
PARISH. LAST SEVERAL RADAR SCANS...AS WELL AS IR IMAGERY...SHOW
THIS ACTIVITY WEAKENING A BIT AS DAYTIME HEATING GRADUALLY WANES.
EVENING GRIDS/ZONES WERE ADJUSTED TO ACCOUNT. LEFT THE OVERNIGHT
GRIDS ALONE AS THE RECENT TREND FOR NOCTURNAL CONVECTION SKIRTING
THE COASTLINE SHOULD AGAIN BE THE RULE WITH RIDGING ALOFT SITUATED
OVER THE WRN GULF STATES. ELSEWHERE TWEAKS TO GRIDS/ZONES WERE
MINOR...UPDATE ALREADY SENT.
25
PREV DISCUSSION... /ISSUED 657 PM CDT WED JUL 29 2015/
AVIATION...VCTS ENDING SOON AT LCH, LFT, AND ARA. VFR WITH AGAIN
VCTS BY MID-AFTERNOON THURSDAY FOR THE SOUTHERN TERMINALS AS
MOISTURE DEEPENS ON THURSDAY INTO FRIDAY.
SWEENEY
PREV DISCUSSION... /ISSUED 320 PM CDT WED JUL 29 2015/
DISCUSSION...
WX MAP SHOWS HIGH PRESSURE RIDGE AT THE SFC ACROSS THE N GULF...WITH
HIGH PRESSURE CONTINUING OVER THE ARKLATEX. LCH WSR88D SHOWS A FEW
SHRA ALONG THE COASTAL PARISHES ...OCCASIONAL TSRA...ALONG THE
I-10 CORRIDOR ACROSS SE TX/S LA THIS AFTERNOON. TEMPS IN THE UPPER
90S ALONG AND N OF I-10...WITH A FEW 100S SPRINKLED ACROSS C LA.
BUT WITH DEWPTS RANGING FROM THE UPPER 60S/LOWER 70S INLAND...KEEPIN
THE HEAT INDEX VALUES 102-106. FOR THIS EVENING...SHRA/TSRA EXPECTED
TO DISSIPATE BY SUNSET...BUT INCREASED MOISTURE FROM THE SE MAY
KEEP ISO SHRA/TSRA ACROSS THE EASTERN COASTAL WATERS.
BY THU AND INTO THE WEEKEND...THE RIDGE ALOFT EXPECTED TO BREAK
DOWN A BIT OVER OUR REGION AND RETROGRADE WESTWARD AS A LONGWAVE
TROF DIGS SOUTH OVER THE EAST COAST. THIS SHOULD ALLOW FOR A WEAK
COOL FRONT TO MOVE FROM THE NORTH. AHEAD OF THE BOUNDARY...SUBSIDENCE
LIKELY TO BUMP UP TEMPS BACK INTO THE UPPER 90S TO NEAR 100 FOR
MOST AREAS N OF I-10. DEWPTS EXPECTED TO BE A COUPLE OF DEGREES
HIGHER IN THE LOWER/MID 70S DUE TO SLIGHTLY INCREASE LOW LEVEL
MOISTURE FROM THE EAST. THUS...HEAT INDEX VALUES LIKELY TO REACH
108-110 FOR THE AFTERNOON HOURS. HEAT ADVISORY MAY BE NEEDED FOR
THE AFTERNOON HOURS FOR THE AREAS IN THE 109-110 RANGE...WHICH
LOOKS TO BE MOST OF LOWER SE TX AND MOST OF C AND S LA.
THE OTHER ISSUE WILL BE THE INITIATION OF SHRA/TSRA AHEAD OF THE
FRONT AS LOW LEVEL MOISTURE AND INSTABILITY INCREASES FROM THE
EAST. TIMING ON THIS WILL LIKELY BE JUST AFTER THE HIGH TEMPERATURES
ARE REACHED...WITH THE BEST CHANCES AND COVERAGE OF SHRA/TSRA EXPECTED
OVER SC LA INTO THE COASTAL WATERS. THIS IS EXPECTED TO CONTINUE
THRU THE EVENING HOURS ACROSS MOST OF S LA...INTO THE COASTAL WATERS
FRI MORNING.
FOR FRI...SLIGHTLY DRIER AIR WITH DEWPTS IN THE 60S ACROSS INLAND
SE TX/C LA WILL LESSEN THE HEAT INDEX VALUES SOMEWHAT. OTHERWISE...NOT
MUCH IF ANY COOLER TEMPS EXPECTED WITH THIS FRONT. BY THE WEEKEND
INTO MON...THE UPPER RIDGE EXPECTED TO CONTINUE RETROGRADING
WESTWARD AS THE LONG WAVE TROF BROADENS OVER THE C AND E U.S. BY
TUE & WED...THE RIDGE ALOFT BUILDS BACK EASTWARD OVER TX/LA...WITH
THE WARMER THAN NORMAL TEMPS RESUMING.
DML
MARINE...
LIGHT AND VARIABLE WINDS ARE EXPECTED TONIGHT...WITH A MORE
PREVALENT WEST TO NORTHWEST FLOW DEVELOPING ON THURSDAY AS A WEAK
FRONTAL BOUNDARY SAGS INTO THE REGION. THIS FRONT...COUPLED WITH
INCREASING MOISTURE FROM THE EASTERN GULF...WILL SIGNIFICANTLY
INCREASE THE CHANCES OF SHOWERS AND THUNDERSTORMS THURSDAY NIGHT
INTO FRIDAY. THE FRONT IS EXPECTED TO STALL NEAR THE COAST...KEEPING
ELEVATED CHANCES OF SHOWERS AND THUNDERSTORMS INTO THE WEEKEND.
DML
&&
.PRELIMINARY POINT TEMPS/POPS...
AEX 77 99 75 97 / 10 20 20 20
LCH 77 98 78 96 / 20 30 30 20
LFT 77 98 77 96 / 20 40 30 30
BPT 77 98 78 97 / 20 20 20 20
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&
$$
AVIATION...11
AREA FORECAST DISCUSSION
NWS CARIBOU ME
104 AM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA ON THURSDAY BRINGING SHOWERS AND
THUNDERSTORMS. AN UPPER DISTURBANCE WILL CROSS NORTHERN MAINE ON
FRIDAY. ANOTHER FRONT WILL PUSH THROUGH THE STATE ON SATURDAY AND
SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH TODAY/...
1 AM UPDATE...ADJUSTED THE POP GRIDS TO PLAY FOR SOME LIGHT
SHOWERS(20%) MOVING ACROSS THE W AND NW BY SUNRISE W/THE WARM
FRONT. THE HRRR 3KM MODEL WAS MATCHING WELL W/THE MOSAIC RADAR
LOOP SHOWING SOME LIGHT SHOWERS IN QUEBEC. KEPT THE MENTION OF FOG
IN THE FORECAST THROUGH THE MORNING W/THE DOWNEAST COAST SEEING
THE MOST DENSE FOG DUE TO SSE FLOW.
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS EXPECTED ON
THURSDAY AS A COLD FRONT PUSHES ACROSS THE STATE. STORMS COULD BE
STRONG TO SEVERE DURING THE AFTERNOON AND EVENING. READ ON FOR
DETAILS...
FOR THURSDAY...THE AFOREMENTIONED STATIONARY FRONT WILL LIFT NORTH
DURING THE AFTERNOON AS LOW PRESSURE SLIDES EASTWARD THROUGH EASTERN
CANADA. A COLD FRONT WILL QUICKLY FOLLOW FROM WEST TO EAST, CROSSING
THE STATE DURING THE LATE AFTERNOON INTO THE EVENING HOURS. SHOWERS
AND THUNDERSTORMS ARE EXPECTED TO DEVELOP OUT AHEAD OF THE COLD
FRONT AND ENTER NORTHWESTERN MAINE AROUND MID AFTERNOON. ALTHOUGH
THERE`S DIFFERING OPINIONS BETWEEN THE MODELS ON HOW MUCH SURFACE
CAPE WILL BE AROUND (500-1200 J/KG ON GFS VS 800-2000 J/KG ON NAM),
AT LEAST THEY AGREE THAT THE BEST INSTABILITY WILL BE ACROSS WESTERN
MAINE, ROUGHLY ALONG AND WEST OF ROUTE 11. HOWEVER, MID-LEVEL LAPSE
RATES LOOK GOOD EVERYWHERE, RUNNING AT 6-7 C/KM. SHEAR WILL INCREASE
THROUGH THE AFTERNOON AND BE 30-35 KT BY EVENING. WOULD EXPECT WINDS
TO BE THE BIGGEST THREAT AS FREEZING LEVELS WILL RISE TO 12+ KFT,
BUT CAN`T RULE OUT SOME LARGE HAIL, ESPECIALLY IN ANY STORMS THAT
MANAGE TO ROTATE. HEAVY RAIN WILL BE A CONCERN AS WELL; PWATS WILL
APPROACH 2 INCHES AS MOISTURE INCREASES IMMEDIATELY AHEAD OF THE
FRONT. CORFIDI VECTORS INDICATE THAT WE COULD SEE TRAINING CELLS
AND/OR SLOW FORWARD MOVEMENT, WHICH WOULD ENHANCE THE FLOOD THREAT.
THE SPC CONTINUES TO INCLUDE ALL OF OUR AREA EXCEPT FAR DOWNEAST IN
A MARGINAL RISK FOR SEVERE WEATHER TOMORROW. HAVE CONTINUED WITH
ENHANCED WORDING IN THE FORECAST.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
SCTD TO NUMEROUS THUNDERSTORMS WILL BE ONGOING ACROSS THE FCST
AREA AT THE BEGINNING OF THE FORECAST PERIOD. SOME OF THE STORMS
COULD PRODUCE HEAVY RAIN...ALONG WITH WITH LARGE HAIL AND DAMAGING
WINDS. ALTHOUGH BY THE EVENING HOURS...THE STORMS SHOULD BE
WEAKENING QUICKLY. A CHANCE OF SHOWERS AND STORMS WILL CONTINUE
ACROSS THE CROWN OF MAINE ON FRIDAY...THEN SPREAD FARTHER SOUTH AS
ANOTHER WEAK UPPER LEVEL SYSTEM PROPAGATES ACROSS NEW ENGLAND ON
SATURDAY. TEMPERATURES WILL REMAIN ABOVE NORMAL WITH HIGHS RANGINGFROM
THE MID 70S TO LOWER 80S.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE EXTENDED MODELS ARE IN GOOD AGREEMENT THROUGH THE PERIOD. THE
PRIMARY WEATHER FEATURES THROUGH THE PERIOD AFFECTING LOCAL
WEATHER WILL BE A HIGH PRESSURE RIDGE TO THE SOUTH...AND A CLOSED
UPPER LEVEL LOW OVER NRN CANADA. UNSETTLED WEATHER THROUGH THE
PERIOD...WITH TROUGHS ABOUT 12 TO 18 HRS APART WILL TRANSIT
THROUGH THE AREA BRINGING SHOWERS AND POSSIBLE TSTMS TO THE AREA.
THE GFS/ECMWF SUN AND MON ARE IN GOOD AGREEMENT WITH SHWRS AND
POSSIBLE TSTMS DURING THE MRNG HRS. BY TUES THE TIMING BEGINS TO
DIFFER WITH THE GFS ABOUT 6 HRS AHEAD OF THE ECMWF.
LOADED SUPERBLEND THROUGH THE PERIOD. LOADED NAWAVE4 FOR SEAS IN
THE COASTAL WATERS...ADDED 15 PERCENT TO WNDS FOR GUSTS OVER LAND
25 PERCENT FOR GUSTS OVER THE COASTAL WATERS.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
NEAR TERM: VFR CONDITIONS EXPECTED TO PREVAIL INTO THURSDAY
MORNING. LOCAL IFR IN FOG IS POSSIBLE TONIGHT, MAINLY ALONG THE
COAST. COASTAL OBSERVATIONS ARE NEARING 100 PERCENT RH, SO FOG
DEVELOPMENT SHOULDN`T BE TOO FAR AWAY. TOUGH CALL ON WHETHER
BANGOR WILL FOG IN. IF THEY DO, THINK THAT IT WILL HOLD OFF UNTIL
AFTER MIDNIGHT AND NOT BE TOO DENSE. A COLD FRONT WILL BRING
SHOWERS AND THUNDERSTORMS TO THE AREA THURSDAY AFTERNOON WITH
MVFR/IFR POSSIBLE WHERE THE STORMS OCCUR.
SHORT TERM: THERE IS SMALL RISK OF STRONG TO SEVERE STORMS ACROSS
THE CWA EARLY THURSDAY EVENING...WHICH COULD PRODUCE HEAVY
RAIN...LARGE HAIL AND STRONG/GUSTY WINDS. ANY STRONG/SEVERE STORMS
SHOULD WEAKEN TO BELOW SEVERE LEVELS BY MIDNIGHT. THEN SCATTERED SHOWERS
AND STORMS WILL AFFECT THE NORTHERN HALF OF MAINE FRIDAY INTO
SATURDAY. REDUCED VSBYS AND CIGS WILL PROBABLY ACCOMPANY THE
STRONGER SHOWERS AND STORMS.
&&
.MARINE...
NEAR TERM: NO HEADLINES ARE ANTICIPATED. MAIN CONCERN WILL BE
RESTRICTED VISIBILITY IN FOG TONIGHT AND THURSDAY MORNING.
SHORT TERM: THERE IS A CHANCE OF THUNDERSTORMS ACROSS THE COASTAL
MAINE ZONES THURSDAY NIGHT. OTHERWISE CONDITIONS SHOULD BE QUITE
WITH WAVES/CIGS STAYING BELOW SCA CRITERIA.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1031 AM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA THIS AFTERNOON WITH
SHOWERS AND THUNDERSTORMS EXPECTED. HIGH PRESSURE BUILDS INTO THE
AREA TONIGHT AND PERSISTS INTO EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
14Z OBS AND VIS SAT INDICATING COLD FRONT CURRENTLY BACK OVER
WESTERN PA STRETCHING INTO CENTRAL WV. REFLECTIVITY SHOWING LINE
OF SHOWERS AHEAD OF THE FRONT OVER WESTERN MD WHERE THE INVERSION
HAS WEAKEN ALREADY THIS MORNING...AND SBCAPE VALUES AROUND 1000
J/KG. 14Z HRRR CONTINUES THIS LINE EAST...WITH ANOTHER AREA
FORMING TO THE SOUTH AND WEST...EVENTUALLY CONNECTING THE TWO OVER
NORTHERN VA LATER THIS AFTN.
EXCEPTIONAL SFC MOISTURE OVER THE AREA MAKES THE GREATEST RISK TODAY
FLASH FLOODING FROM EXCESSIVE RAINFALL. ACTIVITY EXPECTED TO BE
PROGRESSIVE...SO THIS THREAT IS ISOLATED AT BEST. THERE IS A
MARGINAL SEVERE RISK EAST OF THE BLUE RIDGE WHERE DIURNAL TIMING OF
ACTIVITY IS BEST (AFTERNOON). HOWEVER...DEEP MOISTURE JUST LIKE
YESTERDAY WILL LIMIT MID LEVEL LAPSE RATES AND THE SEVERE THREAT.
JUST A LOW WET MICROBURST THREAT WITH THE STRONGEST ACTIVITY.
HOT TODAY WITH MAX TEMPS LOW 90S EAST OF THE BLUE RIDGE WHERE
THICK CLOUDS SHOULD HOLD OUT THE LONGEST. DEWPOINTS IN THE LOW TO
MID 70S WILL RESULT IN MAX HEAT INDICES AGAIN AROUND 100F (JUST
LIKE PREVIOUS TWO DAYS). NO HEAT ADVISORY...BUT IT WILL BE
UNCOMFORTABLE UNTIL THE STORMS HIT/FRONT CROSSES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
COLD FRONT CLEARS THE SERN ZONES THURSDAY EVENING WITH DRIER AIR
TRAILING. DEWPOINTS DROP INTO THE UPR 50S/LOW 60S TONIGHT. MIN
TEMPS 60S WEST OF I-95...LOW 70S EAST.
FRIDAY...H85 TEMPS 16-18 WITH MAX TEMPS AROUND 90F. DEWPOINTS WILL
BE DOWN AROUND 60F...SO NO HEAT INDEX IS EXPECTED. DRY.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
WEAK HIGH PRESSURE BUILDS FRI NIGHT. A PRESSURE TROUGH
ESTABLISHES SAT WITH SOME MOISTURE RETURN AND A SLIGHT CHANCE OF
SHOWERS AND T-STORMS. SFC RIDGE BUILDS AGAIN SUN GIVING WAY TO A
HOT SUNNY DAY. WINDS TURN SWRLY AGAIN ON MON AS PRESSURE TROUGH
ESTABLISHES WITH SOME MOISTURE RETURN AND A RISK OF T-STORMS. A
CDFNT PUSHES THROUGH THE AREA TUE WITH DRY NWRLY WINDS AND A
COOLING TREND MID TO LATE NEXT WEEK AS HIGH PRES BUILDS OVER THE
REGION. IN SUMMARY...HOT WX DURING THE WEEKEND AND EARLY NEXT WEEK
THEN TURNING COOLER MID WEEK ON. PRECIP LOOKS TO BE BELOW NORMAL
NEXT 7 DAYS.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
MAINLY VFR CONDITIONS FOR THE TAF PERIOD. SCT SHOWERS AND TSTMS
WILL MOVE THRU THE TAF SITES THIS AFTN AHEAD OF AN APPROACHING
COLD FRONT. ANY STORM COULD RESULT IN GUSTY...VRB WINDS AND HEAVY
RAIN WHICH COULD REDUCE VIS TO IFR. ANY CONVECTION WILL EXIT TO
THE EAST BY 02Z THIS EVENING...WITH VFR AND DRY CONDITIONS LASTING
THRU FRIDAY.
A SLIGHT RISK OF T-STORMS SAT AND MON. REST OF THE
TIME LOOKS FINE WITH VFR CONDITIONS.
&&
.MARINE...
SCA FOR ALL WATERS STARTING AT 3PM AND CONTINUING UNTIL LATE
EVENING AS A WEAK COLD FRONT WITH HEAVY AND GUSTY THUNDERSTORMS
CROSS. SCA CONTINUES FOR MAIN BAY WATERS FOR NWLY FLOW 15 TO 20 KT
LATE TONIGHT. FLOW DECREASES TO 10 TO 15 KT FRIDAY.
POSSIBLE SCA SATURDAY AFTERNOON. OTHERWISE...WINDS SHOULD REMAIN
BELOW SCA MOST OF THE 5-DAY FCST PERIOD. A SLIGHT RISK OF T-STORMS
SAT AND MON.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 6 AM EDT
FRIDAY FOR ANZ530>533-538>541.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 10 PM EDT
THIS EVENING FOR ANZ535-536-542.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 8 AM EDT
FRIDAY FOR ANZ534-537-543.
&&
$$
SYNOPSIS...BAJ/LFR
NEAR TERM...BAJ/SEARS
SHORT TERM...BAJ
LONG TERM...LFR
AVIATION...BAJ/SEARS/LFR
MARINE...BAJ/LFR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
143 PM EDT THU JUL 30 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 445 AM EDT THU JUL 30 2015
THE LOW PRESSURE SYSTEM THAT BROUGHT THE GUSTY WEST-SOUTHWEST WINDS
TO THE AREA YESTERDAY IS MOVING OUT OF FAR NORTHERN ONTARIO AND INTO
HUDSON BAY. AS THIS IS OCCURRING...IT IS SWEEPING A SURFACE TROUGH
AND SHORTWAVE SOUTHEAST ACROSS THE UPPER GREAT LAKES THIS MORNING
(CURRENTLY STRETCHING SOUTHWEST ACROSS WESTERN LAKE SUPERIOR). THERE
ARE SCATTERED TO BROKEN CLOUDS ALONG AND AHEAD OF THE TROUGH...WITH
THE MOISTURE BEING MOST PROMINENT BETWEEN 800-650MB AS SEEN ON THE
00Z KINL SOUNDING. ARE SEEING LOWER CLOUDS UPSTREAM TO THE NORTH IN
NORTHWESTERN ONTARIO WHERE RAP ANALYSIS DATA IS SHOWING BETTER
MOISTURE BETWEEN 925-850MB. MOST OF THE SHOWERS ASSOCIATED WITH THIS
WAVE ARE IN NORTHWEST ONTARIO AND FAR NORTHERN LAKE SUPERIOR IN
ASSOCIATION WITH THAT DEEPER MOISTURE. STILL SEEING GUSTY WESTERLY
WINDS OVER THE KEWEENAW AND LAKE SUPERIOR...WITH THE KCMX GUSTING TO
27KTS AT 353AM. INLAND AREAS HAVE DECOUPLED AND ARE GENERALLY INT HE
5-10KT RANGE.
AS THE TROUGH OVER THE WESTERN LAKE MOVES ACROSS THE AREA THIS
MORNING...WINDS WILL SHIFT MORE OUT OF THE WEST-NORTHWEST AND BECOME
GUSTY. EXPECT THE STRONGEST GUSTS THROUGH EARLY AFTERNOON...20-25KTS
FOR MOST AREAS AND SLIGHTLY HIGHER OVER THE KEWEENAW...BEFORE
GRADUALLY DIMINISH INTO THE EVENING. NEXT WAVE (CURRENTLY MOVING
INTO SOUTHWESTERN MANITOBA AND NORTHERN NORTH DAKOTA) WILL SLIDE
ACROSS THE AREA LATE THIS MORNING AND THIS AFTERNOON. WITH THE
ASSISTANCE OF DIURNAL HEATING THE THE DEEPER MOISTURE WITH THE
WAVE...WOULD EXPECT SOME SHOWERS/THUNDERSTORMS TO DEVELOP/MOVE INTO
THE AREA THIS AFTERNOON. MODELS FAIRLY CONSISTENT ON THEM OCCURRING
OVER NORTHWEST WISCONSIN AND WESTERN UPPER MICHIGAN NEAR THE
WISCONSIN BORDER...WHERE THE DIURNAL HEATING CAN BE MAXIMIZED AWAY
FROM THE STABILIZING INFLUENCE OF LAKE SUPERIOR. ALSO EXPECT SOME
SHOWERS MOVING OUT OF THE MN ARROWHEAD IN THE AFTERNOON AND ACROSS
WESTERN LAKE SUPERIOR...WHICH COULD AFFECT THE KEWEENAW TOWARD
EVENING...BUT HAVE KEPT THE POPS JUST TO THE WEST FOR NOW.
MODELS VARY SIGNIFICANTLY IN THE AMOUNT OF INSTABILITY (BETWEEN 300-
1400 J/KG)...AND BELIEVE THE ML CAPE VALUES WILL FALL IN THE MIDDLE
GROUND AND AROUND 700-800 J/KG BASED OFF A CONSENSUS AND 03Z SREF
PROBABILITIES ONLY AROUND 10 PERCENT FOR VALUES OVER 1000 J/KG. SO
THERE WILL BE INSTABILITY TO WORK WILL. PLENTY OF SHEAR TO WORK WITH
(0-6KM BULK SHEAR VALUES OF 40-50KTS)...WHICH MAY BE A LITTLE TOO
MUCH WITH THE AMOUNT OF INSTABILITY AVAILABLE. IN ADDITION...THE
CAPE IS FAIRLY TALL/SKINNY (NCAPE VALUES AT OR BELOW 0.1 IN MOST
LOCATIONS)...SO DON/T THINK HAIL IS MUCH OF A THREAT. WOULD LIKELY
BE GUSTY WINDS IF THERE ARE STRONGER STORMS DUE TO THE INVERTED-V
LOOK OF THE SOUNDINGS THIS AFTERNOON (ALTHOUGH DCAPE LOOKS TO BE
BEST INTO NORTHWEST WISCONSIN). ANY SHOWERS/THUNDERSTORMS SHOULD
QUICKLY DIMINISH THIS EVENING AS THE SHORTWAVE DEPARTS AND DIURNAL
HEATING IS LOST.
THE NEXT IN THE SERIES OF SHORTWAVES THAT WILL CONTINUE INTO THE
WEEKEND WILL MOVE INTO THE NORTHWEST CWA TONIGHT. STILL SOME
DDIFFERENCESIN THE WAVE TIMING/TRACK IN THE MODELS...BUT THEY ARE
SHOWING LESS MOISTURE AVAILABLE OVER THE U.P....SO WILL KEEP ANY
POPS OVER LAKE SUPERIOR FOR OVERNIGHT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 526 AM EDT THU JUL 30 2015
THE OVERALL PATTERN AFFECTING THE AREA WILL NOT CHANGE MUCH THROUGH
THE LONG TERM AS A PERSISTENT CLOSED LOW NEAR HUDSON BAY WILL KEEP A
BROAD TROUGH ENTRENCHED OVER MUCH OF ERN CANADA WHILE A BROAD RIDGE
REMAINS ANCHORED OVER THE WRN CONUS. BETWEEN THESE LARGE SCALE
FEATURES A NW FLOW WILL DOMINATE THE GREAT LAKES REGION ALLOWING A
SERIES OF MAINLY WEAK AND MOISTURE STARVED SHORTWAVES TO PASS THRU
AREA RESULTING IN PERIODIC LIGHT PCPN. TYPICALLY...THESE WEAK
SHORTWAVES ARE POORLY RESOLVED BY MODELS WHICH WILL MAKE FOR A
TRICKY FCST IN THE LONG TERM. IT LOOKS LIKE TEMPERATURES WILL BE
NEAR NORMAL THROUGH THE WEEKEND AND THEN PERHAPS TREND BELOW NORMAL
FOR THE EARLY PART OF NEXT WEEK BEHIND AS A MORE AMPLIFIED SHORTWAVE
AND ASSOC COLD FRONT PASS THROUGH THE UPPER GREAT LAKES REGION.
FRI INTO SAT...MOST OF MODELS HINT AT A FEW WEAK SHORTWAVES MOVING
THROUGH THE AREA...ONE FRI MORNING AND ANOTHER FRI NIGHT. WITH
SEVERAL OF THE MODELS SHOWING 100-300 J/KG OF MLCAPE AHEAD OF THESE
WAVES WILL PROBABLY NEED TO MAINTAIN AT LEAST SLIGHT CHC POPS FOR
ISOLD SHRA/TSRA. WITH LIMITED MOISTURE IN NW FLOW EXPECT ANY PCPN
FROM ISOLD CONVECTION TO BE FAIRLY LIGHT.
SATURDAY LOOKS TO BE TRENDING DRIER AS MOST OF THE MODELS INDICATE
SHORTWAVE ENERGY PASSING EAST OF THE AREA SAT MORNING...ALTHOUGH A
POCKET OF HIGHER INSTABILITY NOTED ALONG LAKE MI COUNTIES MAY STILL
WARRANT SLIGHT CHC POPS THERE.
TEMPERATURES FRI THROUGH SAT WILL BE CLOSER TO NORMAL WITH HIGHS IN
THE 70S TO LOWER 80S AND LOWS IN THE 50S TO LOWER 60S.
MODELS COMING INTO A LITTLE BETTER AGREEMENT ON TIMING OF STRONGER
SHORTWAVE COMING DOWN FM SCNTRL CANADA AND ASSOC COLD FROPA FOR SUN
NIGHT/MON TIME FRAME. WILL CONTINUE LOW CHC POPS 30-40 PCT AT THIS
TIME...AND GIVEN STRENGTH OF SHORTWAVE THIS MAY BE BEST OPPORTUNITY
TO SEE WIDEPSREAD ALBEIT LIGHT PCPN. MODELS ADVERTISE BELOW NORMAL
TEMPS FOR MON-WED IN THE WAKE OF THE FROPA AS LATEST 00Z ECMWF SHOWS
8H TEMPS DROPPING TO 4-6C BY MON EVENING AND THEN PERSISTING IN THAT
RANGE INTO WED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 142 PM EDT THU JUL 30 2015
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD
AS LOW-LEVEL AIR MASS REMAINS RELATIVELY DRY. WINDS WILL DECREASE
THIS EVENING AND TONIGHT. THERE MAY BE ISOLATED SHRA NEAR KIWD LATE
THIS AFTERNOON...BUT POTENTIAL OF DEVELOPMENT AND EXPECTED COVERAGE
IS LOW ENOUGH TO ONLY INCLUDE VCSH IN TAF.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 445 AM EDT THU JUL 30 2015
A LOW SPINNING OVER SOUTHERN HUDSON BAY WILL SWEEP A SERIES OF
TROUGH ACROSS LAKE SUPERIOR THROUGH THIS WEEKEND. THE TROUGH THAT
MOVES THROUGH EARLY THIS MORNING WILL SHIFT WINDS TO THE WEST-
NORTHWEST AND COULD PRODUCE A FEW GALE FORCE GUSTS TO 35 KNOTS
THROUGH MID-DAY TODAY. THEN...WINDS ARE EXPECTED TO SLOWLY DIMINISH
THIS AFTERNOON INTO TONIGHT AS THE PRESSURE GRADIENT WEAKENS AND
REMAIN IN THE 10 TO 20KT RANGE INTO THE START OF THE WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...VOSS
AVIATION...TITUS
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1233 PM EDT THU JUL 30 2015
LATEST UPDATE...
HYDRO
.SYNOPSIS...
ISSUED AT 330 AM EDT THU JUL 30 2015
PLEASANT SUMMER WEATHER IS IN STORE OVER THE NEXT FEW DAYS WITH
COMFORTABLE TEMPERATURES AND HUMIDITY LEVELS ALONG WITH PLENTY OF
SUNSHINE AND FRESH WESTERLY BREEZES.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM EDT THU JUL 30 2015
SFC DEW POINTS IN THE 50S HAVE PUSHED INTO SW LWR MI SETTING THE
STAGE FOR SOME STELLAR SUMMER WEATHER THROUGH SATURDAY. HOWEVER
WINDS WILL BE GUSTY IN THE AFTERNOONS WHEN DEEP MIXING AND DRY AIR
MASS/STEEP LAPSE RATES LEADS TO EFFICIENT MOMENTUM TRANSFER OF
STRONGER 25-30 KTS WINDS AT 3000-5000 FT.
OCCASIONAL FAST MOVING SHORTWAVES DIVING SOUTHEAST THROUGH THE
NORTHERN GRTLKS REGION AND ASSOCIATED WEAK SFC TROUGHS MAY SUPPORT A
SLIGHT CHANCE OF A SHOWER OR TSTM BOTH FRIDAY OR SATURDAY. HOWEVER
THE BIG LIMITING FACTOR WILL BE THE MODERATE LOW LEVEL WESTERLY
FLOW OFF LK MI SENDING STABLE AIR WELL INLAND AND PREVENTING ANY
DECENT LOW LEVEL CONVERGENCE. TYPICALLY THIS KEEPS THE BULK OF SW
LWR MI DRY WITH A LOW POTENTIAL USUALLY LIMITED TO JUST THE
NORTHEAST CORNER OF THE CWFA AROUND CLARE.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU JUL 30 2015
SEASONABLE TEMPERATURES ARE ANTICIPATED SATURDAY NIGHT THROUGH
SUNDAY. THERE IS A SMALL CHANCE OF SHOWERS AND THUNDERSTORMS LATE
SATURDAY NIGHT AND SUNDAY WITH A POTENTIALLY BETTER CHANCE FOR
SHOWERS AND THUNDERSTORMS LATE SUNDAY NIGHT OR MONDAY WITH A
STRONGER COLD FRONT AND AS THE LONGWAVE UPPER LEVEL TROUGH
BECOMES MORE AMPLIFIED OVER THE GREAT LAKES REGION.
THE EVOLUTION OF THE UPPER LEVEL PATTERN FEATURING A RIDGE OUT
WEST AND TROUGH OVER THE EAST SUGGESTS THAT TEMPS FOR THE EARLY
TO MIDDLE PORTION OF NEXT WEEK WILL LIKELY AVERAGE A LITTLE BELOW
NORMAL WITH A CONTINUED CHC FOR A FEW SHOWERS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 713 AM EDT THU JUL 30 2015
THE MAIN ISSUE FOR AVIATION INTERESTS TODAY IS THE WINDS. EXPECT
WESTERLY SFC WINDS TO BE SUSTAINED AROUND 15 KNOTS BY NOON WITH
GUSTS REACHING 25 KNOTS THIS AFTERNOON. SFC WINDS WILL DIMINISH
BELOW 10 KNOTS AFTER SUNSET. CLR/VFR CONDITIONS WILL CONTINUE
TODAY AND TONIGHT AND THIS IS HIGH CONFIDENCE DUE TO THE VERY DRY
AIR MASS IN PLACE.
&&
.MARINE...
ISSUED AT 330 AM EDT THU JUL 30 2015
WE ARE STILL LOOKING AT A BORDERLINE SMALL CRAFT ADVISORY/BEACH
HAZARD STATEMENT TODAY. LACK OF COLD ADVECTION SHOULD KEEP THINGS
FROM GETTING TOO OUT OF HAND. THE LATEST RUC WIND GUIDANCE HAS
THE STRONGEST WINDS OVER LK MI OCCURRING THIS MORNING... OUT OF
THE WEST-NORTHWEST... THEN DECREASING AFTER THAT WHILE ACTUALLY
BACKING TO THE SOUTHWEST.
THE IDEA IS THAT ONCE THE STRONGER HEATING AND DEEPER MIXING
COMMENCES OVER THE LAND AREAS THIS AFTERNOON WE END UP SEEING A
REVERSAL IN THE LAND/LAKE PRESSURE AND WIND REGIME... LEADING TO
A DECREASING TREND OVER THE WATER WHILE INCREASING OVER THE LAND.
LATEST BUOY OBSERVATIONS SHOW SOLID 3 FOOTERS OCCURRING AT 3 AM AND
WAVE MODEL GUIDANCE SUGGESTS A BRIEF SPIKE TO AROUND 4 FEET BETWEEN
ABOUT 6 AM AND NOON. WILL MONITOR TRENDS OVER THE NEXT FEW HOURS AND
POST HEADLINES IF BUOY WAVE HEIGHTS CONTINUE TO TREND UP.
&&
.FIRE WEATHER...
ISSUED AT 713 AM EDT THU JUL 30 2015
THE COMBINATION OF DRY FUELS... WARM TEMPERATURES IN THE LOWER TO
MID 80S... A DRY AIR MASS... AND GUSTY WEST WINDS WILL RESULT IN
AN ELEVATED FIRE DANGER OVER THE NEXT FEW DAYS. RAIN CHANCES ARE
EXTREMELY LOW THROUGH SATURDAY AND IT HAS BEEN PREDOMINATELY DRY
FOR THE PAST 10 DAYS.
&&
.HYDROLOGY...
ISSUED AT 1232 PM EDT THU JUL 30 2015
RIVER LEVELS CONTINUE TO FALL AND ARE EXPECTED TO CONTINUE TO FALL
FOR AT LEAST THE NEXT WEEK AS RAINFALL AMOUNTS ARE NOT EXPECTED TO
BE ENOUGH TO CAUSE THE RIVERS TO START RISING.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT UNTIL 4 PM EDT THIS AFTERNOON FOR MIZ037-
043-050-056-064-071.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR
LMZ844>849.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...LAURENS
AVIATION...MEADE
FIRE WEATHER...MEADE
HYDROLOGY...WDM
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
742 AM EDT THU JUL 30 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 445 AM EDT THU JUL 30 2015
THE LOW PRESSURE SYSTEM THAT BROUGHT THE GUSTY WEST-SOUTHWEST WINDS
TO THE AREA YESTERDAY IS MOVING OUT OF FAR NORTHERN ONTARIO AND INTO
HUDSON BAY. AS THIS IS OCCURRING...IT IS SWEEPING A SURFACE TROUGH
AND SHORTWAVE SOUTHEAST ACROSS THE UPPER GREAT LAKES THIS MORNING
(CURRENTLY STRETCHING SOUTHWEST ACROSS WESTERN LAKE SUPERIOR). THERE
ARE SCATTERED TO BROKEN CLOUDS ALONG AND AHEAD OF THE TROUGH...WITH
THE MOISTURE BEING MOST PROMINENT BETWEEN 800-650MB AS SEEN ON THE
00Z KINL SOUNDING. ARE SEEING LOWER CLOUDS UPSTREAM TO THE NORTH IN
NORTHWESTERN ONTARIO WHERE RAP ANALYSIS DATA IS SHOWING BETTER
MOISTURE BETWEEN 925-850MB. MOST OF THE SHOWERS ASSOCIATED WITH THIS
WAVE ARE IN NORTHWEST ONTARIO AND FAR NORTHERN LAKE SUPERIOR IN
ASSOCIATION WITH THAT DEEPER MOISTURE. STILL SEEING GUSTY WESTERLY
WINDS OVER THE KEWEENAW AND LAKE SUPERIOR...WITH THE KCMX GUSTING TO
27KTS AT 353AM. INLAND AREAS HAVE DECOUPLED AND ARE GENERALLY INT HE
5-10KT RANGE.
AS THE TROUGH OVER THE WESTERN LAKE MOVES ACROSS THE AREA THIS
MORNING...WINDS WILL SHIFT MORE OUT OF THE WEST-NORTHWEST AND BECOME
GUSTY. EXPECT THE STRONGEST GUSTS THROUGH EARLY AFTERNOON...20-25KTS
FOR MOST AREAS AND SLIGHTLY HIGHER OVER THE KEWEENAW...BEFORE
GRADUALLY DIMINISH INTO THE EVENING. NEXT WAVE (CURRENTLY MOVING
INTO SOUTHWESTERN MANITOBA AND NORTHERN NORTH DAKOTA) WILL SLIDE
ACROSS THE AREA LATE THIS MORNING AND THIS AFTERNOON. WITH THE
ASSISTANCE OF DIURNAL HEATING THE THE DEEPER MOISTURE WITH THE
WAVE...WOULD EXPECT SOME SHOWERS/THUNDERSTORMS TO DEVELOP/MOVE INTO
THE AREA THIS AFTERNOON. MODELS FAIRLY CONSISTENT ON THEM OCCURRING
OVER NORTHWEST WISCONSIN AND WESTERN UPPER MICHIGAN NEAR THE
WISCONSIN BORDER...WHERE THE DIURNAL HEATING CAN BE MAXIMIZED AWAY
FROM THE STABILIZING INFLUENCE OF LAKE SUPERIOR. ALSO EXPECT SOME
SHOWERS MOVING OUT OF THE MN ARROWHEAD IN THE AFTERNOON AND ACROSS
WESTERN LAKE SUPERIOR...WHICH COULD AFFECT THE KEWEENAW TOWARD
EVENING...BUT HAVE KEPT THE POPS JUST TO THE WEST FOR NOW.
MODELS VARY SIGNIFICANTLY IN THE AMOUNT OF INSTABILITY (BETWEEN 300-
1400 J/KG)...AND BELIEVE THE ML CAPE VALUES WILL FALL IN THE MIDDLE
GROUND AND AROUND 700-800 J/KG BASED OFF A CONSENSUS AND 03Z SREF
PROBABILITIES ONLY AROUND 10 PERCENT FOR VALUES OVER 1000 J/KG. SO
THERE WILL BE INSTABILITY TO WORK WILL. PLENTY OF SHEAR TO WORK WITH
(0-6KM BULK SHEAR VALUES OF 40-50KTS)...WHICH MAY BE A LITTLE TOO
MUCH WITH THE AMOUNT OF INSTABILITY AVAILABLE. IN ADDITION...THE
CAPE IS FAIRLY TALL/SKINNY (NCAPE VALUES AT OR BELOW 0.1 IN MOST
LOCATIONS)...SO DON/T THINK HAIL IS MUCH OF A THREAT. WOULD LIKELY
BE GUSTY WINDS IF THERE ARE STRONGER STORMS DUE TO THE INVERTED-V
LOOK OF THE SOUNDINGS THIS AFTERNOON (ALTHOUGH DCAPE LOOKS TO BE
BEST INTO NORTHWEST WISCONSIN). ANY SHOWERS/THUNDERSTORMS SHOULD
QUICKLY DIMINISH THIS EVENING AS THE SHORTWAVE DEPARTS AND DIURNAL
HEATING IS LOST.
THE NEXT IN THE SERIES OF SHORTWAVES THAT WILL CONTINUE INTO THE
WEEKEND WILL MOVE INTO THE NORTHWEST CWA TONIGHT. STILL SOME
DDIFFERENCESIN THE WAVE TIMING/TRACK IN THE MODELS...BUT THEY ARE
SHOWING LESS MOISTURE AVAILABLE OVER THE U.P....SO WILL KEEP ANY
POPS OVER LAKE SUPERIOR FOR OVERNIGHT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 526 AM EDT THU JUL 30 2015
THE OVERALL PATTERN AFFECTING THE AREA WILL NOT CHANGE MUCH THROUGH
THE LONG TERM AS A PERSISTENT CLOSED LOW NEAR HUDSON BAY WILL KEEP A
BROAD TROUGH ENTRENCHED OVER MUCH OF ERN CANADA WHILE A BROAD RIDGE
REMAINS ANCHORED OVER THE WRN CONUS. BETWEEN THESE LARGE SCALE
FEATURES A NW FLOW WILL DOMINATE THE GREAT LAKES REGION ALLOWING A
SERIES OF MAINLY WEAK AND MOISTURE STARVED SHORTWAVES TO PASS THRU
AREA RESULTING IN PERIODIC LIGHT PCPN. TYPICALLY...THESE WEAK
SHORTWAVES ARE POORLY RESOLVED BY MODELS WHICH WILL MAKE FOR A
TRICKY FCST IN THE LONG TERM. IT LOOKS LIKE TEMPERATURES WILL BE
NEAR NORMAL THROUGH THE WEEKEND AND THEN PERHAPS TREND BELOW NORMAL
FOR THE EARLY PART OF NEXT WEEK BEHIND AS A MORE AMPLIFIED SHORTWAVE
AND ASSOC COLD FRONT PASS THROUGH THE UPPER GREAT LAKES REGION.
FRI INTO SAT...MOST OF MODELS HINT AT A FEW WEAK SHORTWAVES MOVING
THROUGH THE AREA...ONE FRI MORNING AND ANOTHER FRI NIGHT. WITH
SEVERAL OF THE MODELS SHOWING 100-300 J/KG OF MLCAPE AHEAD OF THESE
WAVES WILL PROBABLY NEED TO MAINTAIN AT LEAST SLIGHT CHC POPS FOR
ISOLD SHRA/TSRA. WITH LIMITED MOISTURE IN NW FLOW EXPECT ANY PCPN
FROM ISOLD CONVECTION TO BE FAIRLY LIGHT.
SATURDAY LOOKS TO BE TRENDING DRIER AS MOST OF THE MODELS INDICATE
SHORTWAVE ENERGY PASSING EAST OF THE AREA SAT MORNING...ALTHOUGH A
POCKET OF HIGHER INSTABILITY NOTED ALONG LAKE MI COUNTIES MAY STILL
WARRANT SLIGHT CHC POPS THERE.
TEMPERATURES FRI THROUGH SAT WILL BE CLOSER TO NORMAL WITH HIGHS IN
THE 70S TO LOWER 80S AND LOWS IN THE 50S TO LOWER 60S.
MODELS COMING INTO A LITTLE BETTER AGREEMENT ON TIMING OF STRONGER
SHORTWAVE COMING DOWN FM SCNTRL CANADA AND ASSOC COLD FROPA FOR SUN
NIGHT/MON TIME FRAME. WILL CONTINUE LOW CHC POPS 30-40 PCT AT THIS
TIME...AND GIVEN STRENGTH OF SHORTWAVE THIS MAY BE BEST OPPORTUNITY
TO SEE WIDEPSREAD ALBEIT LIGHT PCPN. MODELS ADVERTISE BELOW NORMAL
TEMPS FOR MON-WED IN THE WAKE OF THE FROPA AS LATEST 00Z ECMWF SHOWS
8H TEMPS DROPPING TO 4-6C BY MON EVENING AND THEN PERSISTING IN THAT
RANGE INTO WED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 742 AM EDT THU JUL 30 2015
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD
AS LOW-LEVEL AIR MASS REMAINS RELATIVELY DRY. WHILE WINDS SHOULD
REMAIN GUSTY TO 20-25KT AT THE MORE EXPOSED KCMX TERMINAL
OVERNIGHT...NOCTURNAL INVERSION WILL RESULT IN LLWS AT KIWD/KSAW.
AFTER SUNRISE AND ONSET OF DAYTIME HEATING...GUSTY WINDS TO 20-25KT
WILL RETURN TO KIWD/KSAW...AND GUSTS WILL INCREASE TO AROUND 30KT AT
KCMX. THERE MAY BE ISOLD SHRA NEAR KIWD LATE THIS AFTN...BUT
POTENTIAL OF DEVELOPMENT AND EXPECTED COVERAGE IS TOO LOW TO INCLUDE
ANY MENTION IN FCST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 445 AM EDT THU JUL 30 2015
A LOW SPINNING OVER SOUTHERN HUDSON BAY WILL SWEEP A SERIES OF
TROUGH ACROSS LAKE SUPERIOR THROUGH THIS WEEKEND. THE TROUGH THAT
MOVES THROUGH EARLY THIS MORNING WILL SHIFT WINDS TO THE WEST-
NORTHWEST AND COULD PRODUCE A FEW GALE FORCE GUSTS TO 35 KNOTS
THROUGH MID-DAY TODAY. THEN...WINDS ARE EXPECTED TO SLOWLY DIMINISH
THIS AFTERNOON INTO TONIGHT AS THE PRESSURE GRADIENT WEAKENS AND
REMAIN IN THE 10 TO 20KT RANGE INTO THE START OF THE WEEKEND. &&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...VOSS
AVIATION...SRF
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
714 AM EDT THU JUL 30 2015
LATEST UPDATE...
AVIATION/FIRE WEATHER
.SYNOPSIS...
ISSUED AT 330 AM EDT THU JUL 30 2015
PLEASANT SUMMER WEATHER IS IN STORE OVER THE NEXT FEW DAYS WITH
COMFORTABLE TEMPERATURES AND HUMIDITY LEVELS ALONG WITH PLENTY OF
SUNSHINE AND FRESH WESTERLY BREEZES.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM EDT THU JUL 30 2015
SFC DEW POINTS IN THE 50S HAVE PUSHED INTO SW LWR MI SETTING THE
STAGE FOR SOME STELLAR SUMMER WEATHER THROUGH SATURDAY. HOWEVER
WINDS WILL BE GUSTY IN THE AFTERNOONS WHEN DEEP MIXING AND DRY AIR
MASS/STEEP LAPSE RATES LEADS TO EFFICIENT MOMENTUM TRANSFER OF
STRONGER 25-30 KTS WINDS AT 3000-5000 FT.
OCCASIONAL FAST MOVING SHORTWAVES DIVING SOUTHEAST THROUGH THE
NORTHERN GRTLKS REGION AND ASSOCIATED WEAK SFC TROUGHS MAY SUPPORT A
SLIGHT CHANCE OF A SHOWER OR TSTM BOTH FRIDAY OR SATURDAY. HOWEVER
THE BIG LIMITING FACTOR WILL BE THE MODERATE LOW LEVEL WESTERLY
FLOW OFF LK MI SENDING STABLE AIR WELL INLAND AND PREVENTING ANY
DECENT LOW LEVEL CONVERGENCE. TYPICALLY THIS KEEPS THE BULK OF SW
LWR MI DRY WITH A LOW POTENTIAL USUALLY LIMITED TO JUST THE
NORTHEAST CORNER OF THE CWFA AROUND CLARE.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU JUL 30 2015
SEASONABLE TEMPERATURES ARE ANTICIPATED SATURDAY NIGHT THROUGH
SUNDAY. THERE IS A SMALL CHANCE OF SHOWERS AND THUNDERSTORMS LATE
SATURDAY NIGHT AND SUNDAY WITH A POTENTIALLY BETTER CHANCE FOR
SHOWERS AND THUNDERSTORMS LATE SUNDAY NIGHT OR MONDAY WITH A
STRONGER COLD FRONT AND AS THE LONGWAVE UPPER LEVEL TROUGH
BECOMES MORE AMPLIFIED OVER THE GREAT LAKES REGION.
THE EVOLUTION OF THE UPPER LEVEL PATTERN FEATURING A RIDGE OUT
WEST AND TROUGH OVER THE EAST SUGGESTS THAT TEMPS FOR THE EARLY
TO MIDDLE PORTION OF NEXT WEEK WILL LIKELY AVERAGE A LITTLE BELOW
NORMAL WITH A CONTINUED CHC FOR A FEW SHOWERS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 713 AM EDT THU JUL 30 2015
THE MAIN ISSUE FOR AVIATION INTERESTS TODAY IS THE WINDS. EXPECT
WESTERLY SFC WINDS TO BE SUSTAINED AROUND 15 KNOTS BY NOON WITH
GUSTS REACHING 25 KNOTS THIS AFTERNOON. SFC WINDS WILL DIMINISH
BELOW 10 KNOTS AFTER SUNSET. CLR/VFR CONDITIONS WILL CONTINUE
TODAY AND TONIGHT AND THIS IS HIGH CONFIDENCE DUE TO THE VERY DRY
AIR MASS IN PLACE.
&&
.MARINE...
ISSUED AT 330 AM EDT THU JUL 30 2015
WE ARE STILL LOOKING AT A BORDERLINE SMALL CRAFT ADVISORY/BEACH
HAZARD STATEMENT TODAY. LACK OF COLD ADVECTION SHOULD KEEP THINGS
FROM GETTING TOO OUT OF HAND. THE LATEST RUC WIND GUIDANCE HAS
THE STRONGEST WINDS OVER LK MI OCCURRING THIS MORNING... OUT OF
THE WEST-NORTHWEST... THEN DECREASING AFTER THAT WHILE ACTUALLY
BACKING TO THE SOUTHWEST.
THE IDEA IS THAT ONCE THE STRONGER HEATING AND DEEPER MIXING
COMMENCES OVER THE LAND AREAS THIS AFTERNOON WE END UP SEEING A
REVERSAL IN THE LAND/LAKE PRESSURE AND WIND REGIME... LEADING TO
A DECREASING TREND OVER THE WATER WHILE INCREASING OVER THE LAND.
LATEST BUOY OBSERVATIONS SHOW SOLID 3 FOOTERS OCCURRING AT 3 AM AND
WAVE MODEL GUIDANCE SUGGESTS A BRIEF SPIKE TO AROUND 4 FEET BETWEEN
ABOUT 6 AM AND NOON. WILL MONITOR TRENDS OVER THE NEXT FEW HOURS AND
POST HEADLINES IF BUOY WAVE HEIGHTS CONTINUE TO TREND UP.
&&
.FIRE WEATHER...
ISSUED AT 713 AM EDT THU JUL 30 2015
THE COMBINATION OF DRY FUELS... WARM TEMPERATURES IN THE LOWER TO
MID 80S... A DRY AIR MASS... AND GUSTY WEST WINDS WILL RESULT IN
AN ELEVATED FIRE DANGER OVER THE NEXT FEW DAYS. RAIN CHANCES ARE
EXTREMELY LOW THROUGH SATURDAY AND IT HAS BEEN PREDOMINATELY DRY
FOR THE PAST 10 DAYS.
&&
.HYDROLOGY...
ISSUED AT 1151 AM EDT WED JUL 29 2015
RIVER LEVELS ARE FALLING AND WELL BELOW BANKFULL. THE MAIN CHANCE OF
RAIN IN THE NEXT 7 DAYS WOULD BE SUNDAY INTO MONDAY NIGHT. LOCALLY
HEAVY RAIN IS POSSIBLE... BUT ONLY PONDING OF WATER IS EXPECTED AWAY
FROM THE RIVERS. RIVERS MAY SHOW RISES... BUT SHOULD NOT REACH BANK
FULL LEVELS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...LAURENS
AVIATION...MEADE
FIRE WEATHER...MEADE
HYDROLOGY...63
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
526 AM EDT THU JUL 30 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 445 AM EDT THU JUL 30 2015
THE LOW PRESSURE SYSTEM THAT BROUGHT THE GUSTY WEST-SOUTHWEST WINDS
TO THE AREA YESTERDAY IS MOVING OUT OF FAR NORTHERN ONTARIO AND INTO
HUDSON BAY. AS THIS IS OCCURRING...IT IS SWEEPING A SURFACE TROUGH
AND SHORTWAVE SOUTHEAST ACROSS THE UPPER GREAT LAKES THIS MORNING
(CURRENTLY STRETCHING SOUTHWEST ACROSS WESTERN LAKE SUPERIOR). THERE
ARE SCATTERED TO BROKEN CLOUDS ALONG AND AHEAD OF THE TROUGH...WITH
THE MOISTURE BEING MOST PROMINENT BETWEEN 800-650MB AS SEEN ON THE
00Z KINL SOUNDING. ARE SEEING LOWER CLOUDS UPSTREAM TO THE NORTH IN
NORTHWESTERN ONTARIO WHERE RAP ANALYSIS DATA IS SHOWING BETTER
MOISTURE BETWEEN 925-850MB. MOST OF THE SHOWERS ASSOCIATED WITH THIS
WAVE ARE IN NORTHWEST ONTARIO AND FAR NORTHERN LAKE SUPERIOR IN
ASSOCIATION WITH THAT DEEPER MOISTURE. STILL SEEING GUSTY WESTERLY
WINDS OVER THE KEWEENAW AND LAKE SUPERIOR...WITH THE KCMX GUSTING TO
27KTS AT 353AM. INLAND AREAS HAVE DECOUPLED AND ARE GENERALLY INT HE
5-10KT RANGE.
AS THE TROUGH OVER THE WESTERN LAKE MOVES ACROSS THE AREA THIS
MORNING...WINDS WILL SHIFT MORE OUT OF THE WEST-NORTHWEST AND BECOME
GUSTY. EXPECT THE STRONGEST GUSTS THROUGH EARLY AFTERNOON...20-25KTS
FOR MOST AREAS AND SLIGHTLY HIGHER OVER THE KEWEENAW...BEFORE
GRADUALLY DIMINISH INTO THE EVENING. NEXT WAVE (CURRENTLY MOVING
INTO SOUTHWESTERN MANITOBA AND NORTHERN NORTH DAKOTA) WILL SLIDE
ACROSS THE AREA LATE THIS MORNING AND THIS AFTERNOON. WITH THE
ASSISTANCE OF DIURNAL HEATING THE THE DEEPER MOISTURE WITH THE
WAVE...WOULD EXPECT SOME SHOWERS/THUNDERSTORMS TO DEVELOP/MOVE INTO
THE AREA THIS AFTERNOON. MODELS FAIRLY CONSISTENT ON THEM OCCURRING
OVER NORTHWEST WISCONSIN AND WESTERN UPPER MICHIGAN NEAR THE
WISCONSIN BORDER...WHERE THE DIURNAL HEATING CAN BE MAXIMIZED AWAY
FROM THE STABILIZING INFLUENCE OF LAKE SUPERIOR. ALSO EXPECT SOME
SHOWERS MOVING OUT OF THE MN ARROWHEAD IN THE AFTERNOON AND ACROSS
WESTERN LAKE SUPERIOR...WHICH COULD AFFECT THE KEWEENAW TOWARD
EVENING...BUT HAVE KEPT THE POPS JUST TO THE WEST FOR NOW.
MODELS VARY SIGNIFICANTLY IN THE AMOUNT OF INSTABILITY (BETWEEN 300-
1400 J/KG)...AND BELIEVE THE ML CAPE VALUES WILL FALL IN THE MIDDLE
GROUND AND AROUND 700-800 J/KG BASED OFF A CONSENSUS AND 03Z SREF
PROBABILITIES ONLY AROUND 10 PERCENT FOR VALUES OVER 1000 J/KG. SO
THERE WILL BE INSTABILITY TO WORK WILL. PLENTY OF SHEAR TO WORK WITH
(0-6KM BULK SHEAR VALUES OF 40-50KTS)...WHICH MAY BE A LITTLE TOO
MUCH WITH THE AMOUNT OF INSTABILITY AVAILABLE. IN ADDITION...THE
CAPE IS FAIRLY TALL/SKINNY (NCAPE VALUES AT OR BELOW 0.1 IN MOST
LOCATIONS)...SO DON/T THINK HAIL IS MUCH OF A THREAT. WOULD LIKELY
BE GUSTY WINDS IF THERE ARE STRONGER STORMS DUE TO THE INVERTED-V
LOOK OF THE SOUNDINGS THIS AFTERNOON (ALTHOUGH DCAPE LOOKS TO BE
BEST INTO NORTHWEST WISCONSIN). ANY SHOWERS/THUNDERSTORMS SHOULD
QUICKLY DIMINISH THIS EVENING AS THE SHORTWAVE DEPARTS AND DIURNAL
HEATING IS LOST.
THE NEXT IN THE SERIES OF SHORTWAVES THAT WILL CONTINUE INTO THE
WEEKEND WILL MOVE INTO THE NORTHWEST CWA TONIGHT. STILL SOME
DDIFFERENCESIN THE WAVE TIMING/TRACK IN THE MODELS...BUT THEY ARE
SHOWING LESS MOISTURE AVAILABLE OVER THE U.P....SO WILL KEEP ANY
POPS OVER LAKE SUPERIOR FOR OVERNIGHT TONIGHT.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 526 AM EDT THU JUL 30 2015
THE OVERALL PATTERN AFFECTING THE AREA WILL NOT CHANGE MUCH THROUGH
THE LONG TERM AS A PERSISTENT CLOSED LOW NEAR HUDSON BAY WILL KEEP A
BROAD TROUGH ENTRENCHED OVER MUCH OF ERN CANADA WHILE A BROAD RIDGE
REMAINS ANCHORED OVER THE WRN CONUS. BETWEEN THESE LARGE SCALE
FEATURES A NW FLOW WILL DOMINATE THE GREAT LAKES REGION ALLOWING A
SERIES OF MAINLY WEAK AND MOISTURE STARVED SHORTWAVES TO PASS THRU
AREA RESULTING IN PERIODIC LIGHT PCPN. TYPICALLY...THESE WEAK
SHORTWAVES ARE POORLY RESOLVED BY MODELS WHICH WILL MAKE FOR A
TRICKY FCST IN THE LONG TERM. IT LOOKS LIKE TEMPERATURES WILL BE
NEAR NORMAL THROUGH THE WEEKEND AND THEN PERHAPS TREND BELOW NORMAL
FOR THE EARLY PART OF NEXT WEEK BEHIND AS A MORE AMPLIFIED SHORTWAVE
AND ASSOC COLD FRONT PASS THROUGH THE UPPER GREAT LAKES REGION.
FRI INTO SAT...MOST OF MODELS HINT AT A FEW WEAK SHORTWAVES MOVING
THROUGH THE AREA...ONE FRI MORNING AND ANOTHER FRI NIGHT. WITH
SEVERAL OF THE MODELS SHOWING 100-300 J/KG OF MLCAPE AHEAD OF THESE
WAVES WILL PROBABLY NEED TO MAINTAIN AT LEAST SLIGHT CHC POPS FOR
ISOLD SHRA/TSRA. WITH LIMITED MOISTURE IN NW FLOW EXPECT ANY PCPN
FROM ISOLD CONVECTION TO BE FAIRLY LIGHT.
SATURDAY LOOKS TO BE TRENDING DRIER AS MOST OF THE MODELS INDICATE
SHORTWAVE ENERGY PASSING EAST OF THE AREA SAT MORNING...ALTHOUGH A
POCKET OF HIGHER INSTABILITY NOTED ALONG LAKE MI COUNTIES MAY STILL
WARRANT SLIGHT CHC POPS THERE.
TEMPERATURES FRI THROUGH SAT WILL BE CLOSER TO NORMAL WITH HIGHS IN
THE 70S TO LOWER 80S AND LOWS IN THE 50S TO LOWER 60S.
MODELS COMING INTO A LITTLE BETTER AGREEMENT ON TIMING OF STRONGER
SHORTWAVE COMING DOWN FM SCNTRL CANADA AND ASSOC COLD FROPA FOR SUN
NIGHT/MON TIME FRAME. WILL CONTINUE LOW CHC POPS 30-40 PCT AT THIS
TIME...AND GIVEN STRENGTH OF SHORTWAVE THIS MAY BE BEST OPPORTUNITY
TO SEE WIDEPSREAD ALBEIT LIGHT PCPN. MODELS ADVERTISE BELOW NORMAL
TEMPS FOR MON-WED IN THE WAKE OF THE FROPA AS LATEST 00Z ECMWF SHOWS
8H TEMPS DROPPING TO 4-6C BY MON EVENING AND THEN PERSISTING IN THAT
RANGE INTO WED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 803 PM EDT WED JUL 29 2015
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD
AS LOW-LEVEL AIR MASS REMAINS RELATIVELY DRY. WHILE GUSTY W TO WSW
WINDS WILL SUBSIDE THIS EVENING AT KIWD/KSAW...EXPECT GUSTS TO
AROUND 25KT TO CONTINUE THRU THE NIGHT AT THE MORE EXPOSED KCMX
SITE. AFTER SUNRISE AND ONSET OF DAYTIME HEATING...GUSTY WINDS TO 20-
25KT WILL RETURN TO KIWD/KSAW...AND GUSTS WILL INCREASE TO AROUND
30KT AT KCMX. THERE MAY BE ISOLD SHRA NEAR KIWD THU AFTN...BUT
POTENTIAL OF DEVELOPMENT AND EXPECTED COVERAGE IS TOO LOW TO INCLUDE
ANY MENTION IN FCST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 445 AM EDT THU JUL 30 2015
A LOW SPINNING OVER SOUTHERN HHUDSONBAY WILL SWEEP A SERIES OF
TROUGH ACROSS LAKE SUPERIOR THROUGH THIS WEEKEND. THE TROUGH THAT
MOVES THROUGH EARLY THIS MORNING WILL SHIFT WINDS TO THE
WEST-NORTHWEST AND COULD PRODUCE A FEW GALE FORCE GUSTS TO 35 KNOTS
THROUGH MID-DAY TODAY. THEN...WINDS ARE EXPECTED TO SLOWLY DIMINISH
THIS AFTERNOON INTO TONIGHT AS THE PRESSURE GRADIENT WEAKENS AND
REMAIN IN THE 10 TO 20KT RANGE INTO THE START OF THE WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...VOSS
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
446 AM EDT THU JUL 30 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 445 AM EDT THU JUL 30 2015
THE LOW PRESSURE SYSTEM THAT BROUGHT THE GUSTY WEST-SOUTHWEST WINDS
TO THE AREA YESTERDAY IS MOVING OUT OF FAR NORTHERN ONTARIO AND INTO
HUDSON BAY. AS THIS IS OCCURRING...IT IS SWEEPING A SURFACE TROUGH
AND SHORTWAVE SOUTHEAST ACROSS THE UPPER GREAT LAKES THIS MORNING
(CURRENTLY STRETCHING SOUTHWEST ACROSS WESTERN LAKE SUPERIOR). THERE
ARE SCATTERED TO BROKEN CLOUDS ALONG AND AHEAD OF THE TROUGH...WITH
THE MOISTURE BEING MOST PROMINENT BETWEEN 800-650MB AS SEEN ON THE
00Z KINL SOUNDING. ARE SEEING LOWER CLOUDS UPSTREAM TO THE NORTH IN
NORTHWESTERN ONTARIO WHERE RAP ANALYSIS DATA IS SHOWING BETTER
MOISTURE BETWEEN 925-850MB. MOST OF THE SHOWERS ASSOCIATED WITH THIS
WAVE ARE IN NORTHWEST ONTARIO AND FAR NORTHERN LAKE SUPERIOR IN
ASSOCIATION WITH THAT DEEPER MOISTURE. STILL SEEING GUSTY WESTERLY
WINDS OVER THE KEWEENAW AND LAKE SUPERIOR...WITH THE KCMX GUSTING TO
27KTS AT 353AM. INLAND AREAS HAVE DECOUPLED AND ARE GENERALLY INT HE
5-10KT RANGE.
AS THE TROUGH OVER THE WESTERN LAKE MOVES ACROSS THE AREA THIS
MORNING...WINDS WILL SHIFT MORE OUT OF THE WEST-NORTHWEST AND BECOME
GUSTY. EXPECT THE STRONGEST GUSTS THROUGH EARLY AFTERNOON...20-25KTS
FOR MOST AREAS AND SLIGHTLY HIGHER OVER THE KEWEENAW...BEFORE
GRADUALLY DIMINISH INTO THE EVENING. NEXT WAVE (CURRENTLY MOVING
INTO SOUTHWESTERN MANITOBA AND NORTHERN NORTH DAKOTA) WILL SLIDE
ACROSS THE AREA LATE THIS MORNING AND THIS AFTERNOON. WITH THE
ASSISTANCE OF DIURNAL HEATING THE THE DEEPER MOISTURE WITH THE
WAVE...WOULD EXPECT SOME SHOWERS/THUNDERSTORMS TO DEVELOP/MOVE INTO
THE AREA THIS AFTERNOON. MODELS FAIRLY CONSISTENT ON THEM OCCURRING
OVER NORTHWEST WISCONSIN AND WESTERN UPPER MICHIGAN NEAR THE
WISCONSIN BORDER...WHERE THE DIURNAL HEATING CAN BE MAXIMIZED AWAY
FROM THE STABILIZING INFLUENCE OF LAKE SUPERIOR. ALSO EXPECT SOME
SHOWERS MOVING OUT OF THE MN ARROWHEAD IN THE AFTERNOON AND ACROSS
WESTERN LAKE SUPERIOR...WHICH COULD AFFECT THE KEWEENAW TOWARD
EVENING...BUT HAVE KEPT THE POPS JUST TO THE WEST FOR NOW.
MODELS VARY SIGNIFICANTLY IN THE AMOUNT OF INSTABILITY (BETWEEN 300-
1400 J/KG)...AND BELIEVE THE ML CAPE VALUES WILL FALL IN THE MIDDLE
GROUND AND AROUND 700-800 J/KG BASED OFF A CONSENSUS AND 03Z SREF
PROBABILITIES ONLY AROUND 10 PERCENT FOR VALUES OVER 1000 J/KG. SO
THERE WILL BE INSTABILITY TO WORK WILL. PLENTY OF SHEAR TO WORK WITH
(0-6KM BULK SHEAR VALUES OF 40-50KTS)...WHICH MAY BE A LITTLE TOO
MUCH WITH THE AMOUNT OF INSTABILITY AVAILABLE. IN ADDITION...THE
CAPE IS FAIRLY TALL/SKINNY (NCAPE VALUES AT OR BELOW 0.1 IN MOST
LOCATIONS)...SO DON/T THINK HAIL IS MUCH OF A THREAT. WOULD LIKELY
BE GUSTY WINDS IF THERE ARE STRONGER STORMS DUE TO THE INVERTED-V
LOOK OF THE SOUNDINGS THIS AFTERNOON (ALTHOUGH DCAPE LOOKS TO BE
BEST INTO NORTHWEST WISCONSIN). ANY SHOWERS/THUNDERSTORMS SHOULD
QUICKLY DIMINISH THIS EVENING AS THE SHORTWAVE DEPARTS AND DIURNAL
HEATING IS LOST.
THE NEXT IN THE SERIES OF SHORTWAVES THAT WILL CONTINUE INTO THE
WEEKEND WILL MOVE INTO THE NORTHWEST CWA TONIGHT. STILL SOME
DDIFFERENCESIN THE WAVE TIMING/TRACK IN THE MODELS...BUT THEY ARE
SHOWING LESS MOISTURE AVAILABLE OVER THE U.P....SO WILL KEEP ANY
POPS OVER LAKE SUPERIOR FOR OVERNIGHT TONIGHT.
.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 239 PM EDT WED JUL 29 2015
IMPACTS...WITH LIMITED CHANCES FOR PRECIP...WILL HAVE TO KEEP
WATCHING FIRE WEATHER.
A LOW PRESSURE SYSTEM WILL HANG OUT OVER HUDSON BAY FROM THU NIGHT
THROUGH AT LEAST THE WEEKEND...SENDING SEVERAL WAVES ACROSS THE AREA
THROUGH DURING TIME. PREDICTABILITY OF THE WAVES IS POOR AS MODELS
STRUGGLE TO CONSISTENTLY RESOLVE THE FEATURES. AVAILABLE MOISTURE IS
ALSO ON THE LOW SIDE...LIMITING PRECIP COVERAGE AND AMOUNTS. WILL
KEEP SLIGHT CHANCE POPS OVER AT LEAST PORTIONS OF THE AREA EACH
PERIOD. TEMPERATURES LOOK TO BE NEAR NORMAL.
FRI LOOKS PRETTY DRY WHEN LOOKING AT THE SFC RH DROPPING INTO THE MID
TO UPPER 30 PERCENT RANGE. WINDS WILL GUSTS TO 20-25MPH...MAKING FOR
SOMEWHAT ELEVATED FIRE WEATHER CONCERNS.
MODELS SHOW THE LOW SHIFTING TO THE SE IN THE EARLY TO MIDDLE PART
OF NEXT WEEK...BUT HOW MUCH AND HOW FAST IS UNCERTAIN. IT DOES LOOK
LIKE BETTER PRECIP CHANCES WILL RESULT FROM THE SHIFT AND SUBSEQUENT
COLD FRONTAL PASSAGE...TIMING OF THAT IS ALSO UNCERTAIN...BUT SUN
NIGHT INTO MON LOOKS LIKE BEST BET FOR NOW. WIDESPREAD PRECIP STILL
MAY NOT OCCUR ALONG THE STRONGER WAVE AND COLD FRONTAL PASSAGE.
TEMPS LOOK TO DROP TO BELOW NORMAL VALUES MON THROUGH WED.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 803 PM EDT WED JUL 29 2015
VFR CONDITIONS WILL PREVAIL AT KIWD/KCMX/KSAW THRU THIS FCST PERIOD
AS LOW-LEVEL AIR MASS REMAINS RELATIVELY DRY. WHILE GUSTY W TO WSW
WINDS WILL SUBSIDE THIS EVENING AT KIWD/KSAW...EXPECT GUSTS TO
AROUND 25KT TO CONTINUE THRU THE NIGHT AT THE MORE EXPOSED KCMX
SITE. AFTER SUNRISE AND ONSET OF DAYTIME HEATING...GUSTY WINDS TO 20-
25KT WILL RETURN TO KIWD/KSAW...AND GUSTS WILL INCREASE TO AROUND
30KT AT KCMX. THERE MAY BE ISOLD SHRA NEAR KIWD THU AFTN...BUT
POTENTIAL OF DEVELOPMENT AND EXPECTED COVERAGE IS TOO LOW TO INCLUDE
ANY MENTION IN FCST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 445 AM EDT THU JUL 30 2015
A LOW SPINNING OVER SOUTHERN HHUDSONBAY WILL SWEEP A SERIES OF
TROUGH ACROSS LAKE SUPERIOR THROUGH THIS WEEKEND. THE TROUGH THAT
MOVES THROUGH EARLY THIS MORNING WILL SHIFT WINDS TO THE
WEST-NORTHWEST AND COULD PRODUCE A FEW GALE FORCE GUSTS TO 35 KNOTS
THROUGH MID-DAY TODAY. THEN...WINDS ARE EXPECTED TO SLOWLY DIMINISH
THIS AFTERNOON INTO TONIGHT AS THE PRESSURE GRADIENT WEAKENS AND
REMAIN IN THE 10 TO 20KT RANGE INTO THE START OF THE WEEKEND.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
330 AM EDT THU JUL 30 2015
LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE
.SYNOPSIS...
ISSUED AT 330 AM EDT THU JUL 30 2015
PLEASANT SUMMER WEATHER IS IN STORE OVER THE NEXT FEW DAYS WITH
COMFORTABLE TEMPERATURES AND HUMIDITY LEVELS ALONG WITH PLENTY OF
SUNSHINE AND FRESH WESTERLY BREEZES.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 330 AM EDT THU JUL 30 2015
SFC DEW POINTS IN THE 50S HAVE PUSHED INTO SW LWR MI SETTING THE
STAGE FOR SOME STELLAR SUMMER WEATHER THROUGH SATURDAY. HOWEVER
WINDS WILL BE GUSTY IN THE AFTERNOONS WHEN DEEP MIXING AND DRY AIR
MASS LEADS TO EFFICIENT MOMENTUM TRANSFER OF STRONGER 25-30 KTS
WINDS AT 3000-5000 FT.
OCCASIONAL FAST MOVING SHORTWAVES DIVING SOUTHEAST THROUGH THE
NORTHERN GRTLKS REGION AND ASSOCIATED WEAK SFC TROUGHS MAY SUPPORT A
SLIGHT CHANCE OF A SHOWER OR TSTM BOTH FRIDAY OR SATURDAY. HOWEVER
THE BIG LIMITING FACTOR WILL BE THE MODERATE WESTERLY FLOW OFF LK MI
SENDING STABLE AIR WELL INLAND AND PREVENTING ANY DECENT LOW LEVEL
CONVERGENCE. TYPICALLY THIS KEEPS THE BULK OF SW LWR MI DRY WITH A
LOW POTENTIAL USUALLY LIMITED TO JUST THE NORTHEAST CORNER OF
THE CWFA AROUND CLARE.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 330 AM EDT THU JUL 30 2015
SEASONABLE TEMPERATURES ARE ANTICIPATED SATURDAY NIGHT THROUGH
SUNDAY. THERE IS A SMALL CHANCE OF SHOWERS AND THUNDERSTORMS LATE
SATURDAY NIGHT AND SUNDAY WITH A POTENTIALLY BETTER CHANCE FOR
SHOWERS AND THUNDERSTORMS LATE SUNDAY NIGHT OR MONDAY WITH A
STRONGER COLD FRONT AND AS THE LONGWAVE UPPER LEVEL TROUGH BECOMES
MORE AMPLIFIED OVER THE GREAT LAKES REGION.
THE EVOLUTION OF THE UPPER LEVEL PATTERN FEATURING A RIDGE OUT WEST
AND TROUGH OVER THE EAST SUGGESTS THAT TEMPS FOR THE EARLY TO MIDDLE
PORTION OF NEXT WEEK WILL LIKELY AVERAGE A LITTLE BELOW NORMAL WITH
A CONTINUED CHC FOR A FEW SHOWERS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1227 AM EDT THU JUL 30 2015
VFR CONDITIONS ARE ANTICIPATED THROUGH THE NEXT 24 HOURS WITH
MOSTLY CLEAR SKIES. WEST WINDS WILL INCREASE TO SUSTAINED AT 15
KTS WITH GUSTS TO 25 KTS FROM LATE THURSDAY MORNING THROUGH
THURSDAY AFTERNOON BEFORE SUBSIDING THURSDAY EVENING.
&&
.MARINE...
ISSUED AT 330 AM EDT THU JUL 30 2015
WE ARE STILL LOOKING AT A BORDERLINE SMALL CRAFT ADVISORY/BEACH
HAZARD STATEMENT TODAY. THE LATEST RUC WIND GUIDANCE HAS THE
STRONGEST WINDS OVER LK MI OCCURRING THIS MORNING... OUT OF THE WEST-
NORTHWEST... THEN DECREASING AFTER THAT WHILE BACKING TO THE
SOUTHWEST.
THE IDEA IS THAT ONCE THE STRONGER HEATING AND DEEPER MIXING
COMMENCES OVER THE LAND AREAS THIS AFTERNOON WE END UP SEEING A
REVERSAL IN THE LAND/LAKE PRESSURE GRADIENT AND WIND REGIME LEADING
TO A DECREASING TREND OVER THE WATER.
LATEST BUOY OBSERVATIONS SHOW SOLID 3 FOOTERS OCCURRING AT 3 AM AND
WAVE MODEL GUIDANCE SUGGESTS A BRIEF SPIKE TO AROUND 4 FEET BETWEEN
ABOUT 6 AM AND NOON. WILL MONITOR TRENDS OVER THE NEXT FEW HOURS AND
POST HEADLINES IF BUOY WAVE HEIGHTS CONTINUE TO TREND UP.
&&
.HYDROLOGY...
ISSUED AT 1151 AM EDT WED JUL 29 2015
RIVER LEVELS ARE FALLING AND WELL BELOW BANKFULL. THE MAIN CHANCE OF
RAIN IN THE NEXT 7 DAYS WOULD BE SUNDAY INTO MONDAY NIGHT. LOCALLY
HEAVY RAIN IS POSSIBLE... BUT ONLY PONDING OF WATER IS EXPECTED AWAY
FROM THE RIVERS. RIVERS MAY SHOW RISES... BUT SHOULD NOT REACH BANK
FULL LEVELS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS...MEADE
SHORT TERM...MEADE
LONG TERM...LAURENS
AVIATION...LAURENS
HYDROLOGY...63
MARINE...MEADE
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
315 AM CDT THU JUL 30 2015
.SHORT TERM: (THROUGH THIS AFTERNOON)
ISSUED AT 314 AM CDT THU JUL 30 2015
"COLD" FRONT IS NOW ALMOST ALL THE WAY THROUGH THE CWFA. TOUGH TO
REALLY PICK IT OUT, BUT EVEN FARMINGTON IS REPORTING NORTHWESTERLY
WINDS AT THIS HOUR. IT MIGHT BE HUNG UP OVER THE FAR SOUTHERN
PORTIONS OF IRON AND REYNOLDS THOUGH. REGARDLESS, WE`RE AT PEAK
HEATING RIGHT NOW, AND WE CAN`T SEEM TO CRACK 105 DEGREES ON THE
HEAT INDEX, SO WILL BE DROPPING THE EXCESSIVE HEAT WARNING AT 400
PM. WIDELY SCATTERED CONVECTION IS FIRING ALONG THE FRONT, BUT IN
SOUTHEAST MISSOURI AND SOUTHERN ILLINOIS, BUT A WEAK CAP HAS
DEVELOPED OVER THE AREA ACCORDING TO RAP SOUNDINGS SO I DON`T EXPECT
ANY CONVECTION FOR THE REST OF THE DAY AND EVENING HOURS EXCEPT
POTENTIALLY IN THE VICINITY OF THE FRONT. ANY STORMS THAT DO AFFECT
OUR SOUTHERN CWFA SHOULD BE OUT OF THE AREA OR DISSIPATED BY EARLY
EVENING. SLIGHTLY COOLER, BUT SUBSTANTIALLY DRIER AIR WILL FILTER
SOUTH OVERNIGHT. STUCK CLOSE TO ENSEMBLE GUIDANCE FOR LOWS TONIGHT
WHICH ARE ACTUALLY A LITTLE WARMER THAN OPERATIONAL MET/MAV. WANTED
TO BE A LITTLE MORE CONSERVATIVE ON THE "COOL DOWN" SINCE IT IS JULY
AFTER ALL, AND THIS ISN`T EXACTLY AN ARCTIC FRONT.
TRUETT
.LONG TERM: (TONIGHT THROUGH WEDNESDAY)
ISSUED AT 314 AM CDT THU JUL 30 2015
THE SFC RIDGE BUILDING INTO THE REGION TODAY WILL ALREADY BE S OF
THE AREA BY MID-DAY FRI. THIS WILL RETURN THE REGION TO SWLY FLOW
BRIEFLY AHEAD OF THE NEXT CDFNT. HAVE TRENDED SLIGHTLY WARMER FRI
OVER TEMPS FOR TODAY BECAUSE OF THIS. FORCING ASSOCIATED WITH THIS
FNT IS RATHER WEAK WITH NWLY 850MB FLOW AHEAD OF THE FNT. THEREFORE,
DO NOT ANTICIPATE MUCH IN THE WAY OF CONVECTION WITH THIS FNT.
HOWEVER, WITH WARM TEMPS AND DEWPOINT POOLING ALONG/AHEAD OF THE
FNT, A FEW TSRA ARE POSSIBLE. PRECIP CHANCES ARE BETTER WITH THE
NEXT CDFNT SAT NIGHT INTO SUN AND POSSIBLY INTO NEXT WEEK.
WHILE MDLS ARE IN FAIRLY GOOD AGREEMENT THRU SAT, DIFFERENCES
GREATLY INCREASE IN THE EXTD. HAVE THEREFORE KEPT POPS LOWER DUE TO
THE UNCERTAINTY. KEPT TEMPS TRENDING SLIGHTLY WARMER THAN A
COMPROMISE AMONG MDL GUIDANCE.
TILLY
&&
.AVIATION: (FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 508 PM CDT WED JUL 29 2015
COLD FRONT HAS M0VED THROUGH THE AREA WITH HIGH PRESSURE SETTLING
IN FROM THE NORTHERN ROCIKES TO THE LOWER MISSOURI VALLEY. DEW
POINTS IN THE 60S WILL BE A WELCOME CHANGE. LIGHT WEST TO
NORTHWEST WIND AND VFR CONDITIONS.
SPECIFICS FOR KSTL: HIGH PRESSURE MOVING WITH DRIER AIR. LIGHT
WEST TO NORTHWEST WIND THROUGH THURSDAY. VFR.
JPK
&&
.PRELIMINARY POINT TEMPS/POPS:
SAINT LOUIS 90 69 91 69 / 0 0 10 20
QUINCY 88 65 89 64 / 0 0 20 20
COLUMBIA 89 66 90 66 / 5 0 10 20
JEFFERSON CITY 90 66 91 67 / 5 0 10 20
SALEM 88 66 89 66 / 0 0 10 20
FARMINGTON 87 63 89 67 / 5 0 5 10
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1143 PM CDT WED JUL 29 2015
.SHORT TERM...(TONIGHT THROUGH SATURDAY)
ISSUED AT 249 PM CDT WED JUL 29 2015
FORECAST CONCERNS IN THE VERY SHORT TERM WILL BE ANY LIGHT
SPRINKLES IN SOUTHEAST NEBRASKA...THEN TEMPERATURES...AND CHANCE
OF THUNDERSTORMS FRIDAY INTO SATURDAY.
WATER VAPOR SATELLITE IMAGERY SHOWED THE MAIN SYNOPTIC FEATURE OF
INTEREST WAS THE CLOSED LOW PRESSURE CENTER OVER ONTARIO CANADA
WITH THE MID LEVEL MOISTURE PLUME FROM THE BAJA OF CALIFORNIA
THROUGH THE FOUR CORNERS REGION INTO THE CENTRAL PLAINS AND OHIO
RIVER VALLEY. OF NOTE ON THE H3 MAP WAS THE H3 JET OVER THE
NORTHERN/CENTRAL PLAINS INTO THE GREAT LAKES. AT H5...THE
STRONGEST HEIGHT FALLS WERE ASSOCIATED WITH THE CLOSED LOW IN
CANADA AND THESE TRAILED SOUTHWARD INTO THE PLAINS. MID LEVEL
MOISTURE WAS NOTED AT H5 AT KLBF ON THEIR 12Z SOUNDING. THE BETTER
H7 AND H85 MOISTURE WAS SUPPRESSED TO THE SOUTH ACROSS KANSAS.H85
DEWPOINTS OF 14-16 DEG C FROM NEW MEXICO INTO TX/OK/SOUTHERN KS.
THERE IS A POCKET OF WEAK WARM AIR ADVECTION/WEAKENING H85-H7
FRONTOGENESIS WITH PATCHY MID LEVEL CUMULUS AND A FEW
SPRINKLES. ALSO HAVE SOME WEAK RIGHT ENTRANCE JET LIFT. HAVE
ADDED SOME SPRINKLES WITH THESE FEATURES. MOST OF THE MODELS WERE
DRY...HOWEVER THE HRRR AND THE HRRRX DID HINT AT THIS IN THEIR
ASSIMILATED REFLECTIVITY FIELDS. SURFACE HIGH PRESSURE PREVAILS
FOR THE REST OF TONIGHT INTO THURSDAY. LOWS TONIGHT IN THE UPPER
50S TO LOWER 60S. HIGH THURSDAY SHOULD TOP OUT IN THE UPPER 80S TO
LOWER 90S.
DEEPER MOISTURE RETURNS THURSDAY NIGHT AND FRIDAY WITH A WEST TO
EAST INSTABILITY AXIS DEVELOPING AND MOISTURE POOLING ALONG THIS
AXIS. WE ARE IN NORTHWEST LOW ALOFT AND THE FORCING IS WEAK.
INSTABILITY DOES INCREASE TO 2000 J/KG THURSDAY NIGHT AND 4000
J/KG FRIDAY. DO MENTION ISOLATED TO SCATTERED THUNDERSTORMS
FRIDAY AND SATURDAY WITH WEAK FORCING IN THIS PATTERN. HIGH
TEMPERATURES CONTINUE IN THE MID TO UPPER 80S EACH DAY.
.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 249 PM CDT WED JUL 29 2015
THE UNSETTLED PATTERN CONTINUES IN THE EXTENDED AS RIDGE AMPLIFIES
TO THE WEST WITH THE MID TROPOSPHERIC TROF TO OUR EAST AND WE
REMAIN IN NORTHWEST FLOW ALOFT. THE EC TRIES TO BRING A DEEPER
WAVE ACROSS THE ROCKIES INTO THE PLAINS MONDAY NIGHT AND TUESDAY
WITH MORE ROBUST PRECIPITATION TUESDAY NIGHT INTO WEDNESDAY.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1142 PM CDT WED JUL 29 2015
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD ALONG WITH
SOUTHWESTERLY SFC WINDS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...ZAPOTOCNY
LONG TERM...ZAPOTOCNY
AVIATION...KERN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
148 AM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE REGION LATE TONIGHT INTO
TOMORROW MORNING BRINGING THE CHANCE FOR SHOWERS AND THUNDERSTORMS
ACROSS THE REGION. FRIDAY IS EXPECTED TO BE SLIGHTLY COOLER AND
DRIER.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
940 PM UPDATE...CURRENT FORECAST IN GOOD SHAPE JUST MADE MINOR
OVERNIGHT TEMPERATURE ADJUSTMENTS. SFC COLD FRONT CURRENTLY
BETWEEN DETROIT AND CLEVELAND WITH WEAK CONVECTION OVER EASTERN
OHIO. LATEST HRRR INDICATES CONVECTION ASSOCIATED WITH THIS
BOUNDARY WILL MOVE INTO THE WESTERN CWA AROUND 12Z THEN REACH THE
CENTRAL PTN OF THE FA INCLUDING BGM AROUND 15Z, THIS TIMING
MATCHES WELL WITH CURRENT POP FORECAST.
300 PM EDT UPDATE...
ANOTHER NICE SUMMER DAY IS PRESENT OVER CENTRAL NY AND NORTHEAST PA
THIS AFTERNOON. CIRRUS CLOUDS ARE OVERSPREADING THE REGION AS
MOISTURE IS ROUNDING THE OUTER EDGE OF THE UPPR RIDGE. A CU MID LVL
DECK IS DEVELOPING AS WELL DUE TO DIURNAL HEATING AND SOME LINGERING
MOISTURE. 850MB TEMPS WILL RISE TO NEAR 20 DEGREES C... WHICH SHOULD
RESULT TEMPS REACHING THE UPPR 80S TO LOW 90S WITH NO PROBLEM.
CLOUD COVERAGE WILL INCREASE OVERNIGHT WITH THE APPROACHING UPPR LVL
TROUGH AS IT ADVECTS MORE MOISTURE INTO THE REGION. THE WAA WILL
KEEP TEMPS WELL ABOVE SEASONAL AVERAGE IN THE 70S OVERNIGHT.
THE MENTIONED UPPR LVL TROUGH WILL BRING A COLD FRONT ACROSS THE
REGION STARTING LATE TONIGHT/NEAR SUNRISE TIME FRAME. THIS FRONT IS
FAIRLY WEAK AS VERY LITTLE CHANGES IN THE 1000-500MB HEIGHT
THICKNESS WILL OCCUR. PWAT VALUES WILL BE FAIRLY HEIGHT TOMORROW...
NEAR 2 INCHES. WITH THIS ENVIRONMENT... EXPECT SOME HEAVY RAIN
SHOWERS AS THIS FRONT PASSES. EMBEDDED THUNDER WILL BE POSSIBLE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
300 PM EDT UPDATE...
THE COLD FRONT IS EXPECTED TO MOVE EAST AND REACH I-81 ROUGHLY
AROUND 18Z TOMORROW... THEN BE EAST OUT OF THE REGION BY 00Z FRIDAY.
SHOWERS AND THUNDERSTORMS ARE LIKELY ALONG AND AHEAD OF THE COLD
FRONT. DEPENDING ON HOW QUICKLY THE FRONT MOVES THROUGH THE CWA WILL
DEPEND ON HOW STRONG THUNDERSTORMS MAY BECOME. THE SLOWER THE FRONT
MOVES THROUGH THE AREA THE MORE UNSTABLE THE ATMOSPHERE WILL BE ABLE
TO BECOME. SBCAPE AT BEST MAY BE AROUND 1800 J/KG... LOW LVL LAPSE
RATES WILL BE ROUGHLY 6.5 C/KM... MID LVL LAPSE RATES WILL BE ON THE
WEAK SIDE NEAR 5 C/KM... AND 0-6-KM BULK SHEAR VALUES WILL BE ON THE
LOW SIDE RANGING 15-25 KNOTS. PWAT VALUES WILL BE HIGH... AROUND 2
INCHES. FROM THE STATED PARAMETERS ABOVE... EXPECT MOSTLY HEAVY
SHOWERS AND THUNDERSTORMS TO DEVELOP TOMORROW AFTERNOON. A FEW
THUNDERSTORMS MAY BE ABLE TO PRODUCE A FEW GUSTY WINDS... BUT HEAVY
RAIN IS EXPECTED TO BE THE MAIN THREAT.
BEHIND THE FROPA EXPECT CLOUD COVERAGE TO DISSIPATE FAIRLY QUICKLY
AS DRY AIR WILL FOLLOW. EXPECT BY 03Z SKIES SHOULD BECOME MOSTLY
CLEAR... AND TEMPS WILL RETURN TO MORE OF A SEASONAL AVERAGE FOR
THIS TIME OF THE YEAR IN THE LOW TO MID 60S.
FRIDAY WILL BE FAIRLY QUIET AS WEAK HIGH PRESSURE DEVELOPS IN THE
WAKE OF THE TROUGH. THIS WILL BE SHORT LIVED AS THE NEXT SYSTEM TO
IMPACT THE REGION IS EXPECTED TO MOVE THROUGH STARTING EARLY SAT
MORNING. IT LOOKS LIKE SCATTERED SHOWERS AND THUNDERSTORMS MAY BE
POSSIBLE THROUGH THE DAY ON SAT AS A WEAK FRONT/SFC TROUGH MOVES
THROUGH.
TEMPS ARE EXPECTED TO BE AT OR SLIGHTLY ABOVE THE SEASONAL AVERAGE
THROUGH THE FORECAST PERIOD.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
2 PM UPDATE...
FOLLOWED LATEST WPC GUIDANCE. TEMPERATURES NEAR NORMAL. UNSETTLED
BUT ONLY LOW CHC TO SCHC POPS. MODELS DO NOT AGREE ON TIMING OF
WEAK SYSTEMS MOVING THROUGH. AT UPPER LEVELS A BROAD TROUGH. THE
BEST CHANCE LOOKS LIKE MONDAY OR TUESDAY WITH A DECENT COLD FRONT
FOR EARLY AUGUST.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
SITES CURRENTLY VFR HOWEVER OVERNIGHT CLOUDS INCREASE AHEAD OF AN
APPROACHING FRONT. ALSO, AS MOISTURE IS DRAWN UP AHEAD OF THIS
FRONT IN THE LOW LEVELS WE EXPECT A STRATUS DECK TO FORM BY
MORNING AND AFFECT AVP/BGM/ELM WITH MVFR CIGS. THE ACTUAL FRONT
ITSELF WILL MOVE ACROSS THE AREA WEST TO EAST THURSDAY MORNING
BRINGING A PERIOD OF SHOWERS TO THE TAF SITES. THERE IS THE RISK
OF THUNDER AS WELL HOWEVER DUE TO THE MORNING TIMING OF THE FRONT
THE CHANCES OF THIS OCCURRING IS NOT HIGH ENOUGH TO WARRANT
INCLUSION IN TAFS. THE FRONT CLEARS ALL TAF SITES BY EARLY TO MID
AFTERNOON WITH CIGS IMPROVING TO VFR.
WINDS WILL BE S TO SW OVERNIGHT UNDER 10 KNOTS AND W-NW 10-12
KNOTS WITH GUSTS 15-20 KNOTS HIGHER TERRAIN SITES BY THU PM.
.OUTLOOK...
THURSDAY NGT TO MONDAY...MAINLY VFR. POSSIBLY BRIEF MVFR IN
SHOWERS. ALSO RESTRICTIONS IN MORNING VALLEY FOG AT KELM POSSIBLE.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...KAH
NEAR TERM...KAH/RRM
SHORT TERM...KAH
LONG TERM...TAC
AVIATION...PCF
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
334 PM EDT THU JUL 30 2015
.SYNOPSIS...
LOW PRESSURE OFF THE SOUTHEAST COAST WILL SLOWLY SHIFT TO THE
NORTHEAST AWAY FROM THE AREA AS A COLD FRONT MOVES INTO THE AREA
FRIDAY. THIS FRONT WILL STALL OVER THE WEEKEND BEFORE DISSIPATING
EARLY NEXT WEEK. BERMUDA HIGH PRESSURE WILL EXPAND WESTWARD TUESDAY
THROUGH THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 330 PM THURSDAY...LOW PRESSURE IS LOCATED A LITTLE OVER 200
MILES EAST OF BEAUFORT SOUTH CAROLINA. THIS LOW HAS BEEN BATTLING
DRY AIR IMPINGING ON THE CIRCULATION FROM THE NORTH. THIS...PLUS
NORTHEASTERLY SHEAR HAS PREVENTED SIGNIFICANT DEEPENING VIA WARM
CORE/TROPICAL PROCESSES. THE 12Z GFS AND NAM APPEAR FAR TOO EAGER
TO ABSORB THE LOW AND MID LEVEL CIRCULATION WITHIN THE BROADER
WIND FIELD AROUND THE COLD FRONT APPROACHING FROM THE WEST
TONIGHT. THE 17Z RUN OF THE RUC APPEARS MUCH MORE REASONABLE AS
ITS INITIALIZED POSITION OF THE LOW IS MUCH CLOSER TO WHERE IT
APPEARS ON VISIBLE SATELLITE. COMPARED TO THE NAM AND GFS THIS
MEANS A SLOWER VEERING OF SURFACE WIND DIRECTIONS...LIGHTER
OVERALL WIND SPEEDS...AND A DELAY IN ANY PRECIPITATION CHANCES
NEAR THE COAST UNTIL AFTER MIDNIGHT.
ISOLATED SHOWERS ACROSS PENDER COUNTY SHOULD DIE A QUICK DEATH OVER
THE NEXT FEW HOURS AS DRY AIR ALOFT WINS THE GAME. FARTHER INLAND
WHERE BETTER MOISTURE EXISTS WITHIN THE 850-700 MB LAYER...SCATTERED
SHOWERS AND EVEN A FEW THUNDERSTORMS ARE POSSIBLE NEAR AND WEST OF
I-95 THROUGH THE LATE AFTERNOON. THESE SHOWERS AND STORMS WILL
BECOME MORE ISOLATED AFTER SUNSET AS THE SURFACE STABILIZES AND
CONVECTION WILL BE FORCED TO USE 850 MB AS A LIFTING LAYER...WITH
LESS INSTABILITY AND ONLY THE INCOMING FRONT AS A CONVERGENT
BOUNDARY. THE COLD FRONT ITSELF IS MAKING QUICK PROGRESS
SOUTHEASTWARD THROUGH WESTERN VIRGINIA AND NORTH CAROLINA...AND
SHOULD BE NEAR THE COAST AT SUNRISE FRIDAY.
LOWS SHOULD FALL INTO THE 72-76 RANGE OVERNIGHT...NOT AS COOL AS ONE
MIGHT THINK WITH AN INCOMING FRONT. A FEW MORE CLOUDS THAN WE SAW
THIS MORNING PLUS LOW-LEVEL MOISTURE POOLED NEAR THE BOUNDARY SHOULD
PREVENT TEMPS FROM FALLING TOO FAR.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
AS OF 330 PM THURSDAY...A COLD FRONT WILL SHIFT OVER THE FORECAST
AREA ON FRIDAY AND WILL REMAIN THROUGH THE PERIOD.THE MOISTURE
WILL INCREASE BUT A VERY TIGHT GRADIENT WILL BE SEEN WITH +2 INCH
PW ALONG THE COAST TO 1.5 INCHES WEST OF INTERSTATE 95. MODELS ARE
SHOWING THE BEST CONVECTION FROM 15 UTC INTO THE OVERNIGHT HOURS
WITH A 50% CHANCE OF THUNDERSTORMS ESPECIALLY OVER THE EAST HALF
OF THE FORECAST AREA. THE CONVECTION CHANCES WILL SLOWLY BACK TO
30 PERCENT BY LATE SATURDAY NIGHT. HIGHS WILL RANGE FROM THE MID
90S INLAND UNTIL THE CLOUD COVER AND CONVECTION BEGINNING AND TO
THE UPPER 80S AT THE BEACHES.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 330 PM THURSDAY...UNSETTLED WEATHER TO START THE PERIOD WILL
GIVE WAY TO WARMING TEMPERATURES THROUGH THE MIDDLE OF NEXT WEEK.
STALLED COLD/STATIONARY FRONT WILL BE IN THE VICINITY
SUNDAY...PROBABLY ALIGNED RIGHT ALONG OR JUST OFF THE COAST...BEFORE
WASHING OUT AND DISSIPATING ON MONDAY. VERY HIGH PWATS AND SOME
TROPICAL MOISTURE WILL BE LURKING JUST OFF THE COAST...SO AS THIS
FRONT LIFTS BACK NORTH MONDAY AND FALLS APART...INCREASING PRECIP
CHANCES WILL OVERSPREAD THE AREA FROM SE TO NW. HOWEVER...THE BULK
OF THIS PRECIP IS STILL EXPECTED TO REMAIN OFFSHORE. HOWEVER...WILL
CONTINUE THE MDT-CHC POP ALONG THE COAST WITH LOW-CHC INLAND FOR
SUN/MON ALONG WITH TEMPS AROUND NORMAL FOR EARLY AUGUST.
THEREAFTER...LARGE RIDGE ACROSS THE SOUTHERN TIER WILL EXPAND NE
INTO WEDNESDAY BRINGING REDUCED PRECIP CHANCES LOCALLY...BUT WITH
TEMPS RISING TO ABOVE NORMAL ONCE AGAIN. THIS HEAT MAY BE SHORT
LIVED THOUGH AS A COLD FRONT IS PROGGED TO PUSH SOUTH
THURSDAY...WITH VERY DEEP TROUGHING IN ITS WAKE ACROSS THE EASTERN
CONUS. THIS WILL BRING COOLER TEMPS AND ONCE AGAIN INCREASED PRECIP
CHANCES AT THE END OF THE PERIOD.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/... AS OF 18Z...LFC`S
COMING DOWN NORTH OF THE REGION. MAY SEE CONVECTION IN PENDER AND
NEW HANOVER COUNTIES THIS AFTERNOON...BUT WILL STICK WITH VCSH DUE
TO COVERAGE AND INTENSITY. MAINLY AN EAST NORTHEAST WIND THIS
AFTERNOON ALONG THE COAST...LIGHT INLAND. TONIGHT...THE NAM WANTS
TO KEEP CONVECTION GOING AS THE FRONT LAYS OVER THE CWA. DUE TO
LACK OF FORCING...SHOULD SEE CONVECTION ENDING FOR DIURNAL REASONS
AFTER 02Z WITH ONLY ISOLATED ACTIVITY OVERNIGHT. FRIDAY...EXPECT
CONVECTION TO FIRE FAIRLY EARLY...MAINLY OVER THE EASTERN HALF OF
THE REGION. POST FRONTAL LIGHT NORTHERLY FLOW IS FORECAST.
EXTENDED OUTLOOK...PREDOMINANTLY VFR THROUGH THE PERIOD WITH A
SLIGHT CHANCE AFTERNOON SHRA/TSRA. BEST CHANCE SHRA/TSRA FRIDAY AND
SATURDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 330 PM THURSDAY...LOW PRESSURE IS LOCATED A LITTLE OVER 200
MILES EAST OF BEAUFORT SOUTH CAROLINA. THIS LOW HAS BEEN BATTLING
DRY AIR INPINGING ON THE CIRCULATION FROM THE NORTH. THE 12Z GFS
AND NAM MODELS APPEAR FAR TOO EAGER TO ABSORB THE LOW INTO THE
COLD FRONT APPROACHING FROM THE WEST TONIGHT. THE 17Z RUN OF THE
RUC MODEL APPEARS MUCH MORE REASONABLE AS ITS INITIALIZED POSITION
OF THE LOW IS MUCH CLOSER TO WHERE IT APPEARS ON VISIBLE
SATELLITE. COMPARED TO THE NAM AND GFS THIS MEANS A SLOWER VEERING
OF SURFACE WIND DIRECTIONS...LIGHTER OVERALL WIND SPEEDS...AND A
DELAY IN ANY PRECIPITATION CHANCES NEAR THE COAST UNTIL LATE
TONIGHT.
SEAS CURRENTLY RANGE FROM 2-3 FEET INSIDE 20 MILES FROM SHORE...TO
AS HIGH AS 4 FEET OUT AT THE FRYING PAN SHOALS BUOY. THE WAVE
SPECTRUM IS DOMINATED BY SWELL ENERGY AT AROUND 7-8 SECONDS PERIOD.
THIS SOUTHEASTERLY SWELL IS BEING GENERATED BY THE LOW OFF THE SOUTH
CAROLINA COAST...AND SHOULD REMAIN THE DOMINANT WAVE SET TONIGHT.
SOME OF THESE 4-FOOTERS SHOULD MAKE IT INSIDE THE COASTAL WATERS
TONIGHT...ESPECIALLY NEAR CAPE FEAR.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 PM THURSDAY...A COLD FRONT WILL STALL ALONG THE COAST
AND WINDS AREA EXPECTED TO REMAIN AT 10 KNOTS OR LESS AND
DIRECTIONS WILL BE VARIABLE OVER THE PERIOD. SEA HEIGHTS ARE
EXPECTED TO RANGE BETWEEN 2 AND 3 FEET WITH A FEW 4 FOOTERS AT 20
MILES OF THE COAST MAINLY FROM FRYING PAN SHOALS NORTHWARD.
LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 330 PM THURSDAY...WEAKENING COLD FRONT WILL DISSIPATE JUST
INLAND FROM THE COASTAL WATERS SUNDAY INTO MONDAY...ALLOWING FOR
BERMUDA HIGH PRESSURE TO ONCE AGAIN BECOME THE DOMINANT SYNOPTIC
FEATURE. THIS WILL CREATE SW WINDS OF 10-15 KTS...WHICH WILL BE
PERSISTENT WITH LITTLE FLUCTUATION THROUGH THE PERIOD. WAVE
AMPLITUDES WILL INCREASE...ESPECIALLY EARLY NEXT WEEK...AS A
FAIRLY SIGNIFICANT SOUTHERLY SWELL OF 5-6 FT ENTERS THE SPECTRUM
AND COMBINES WITH THE SW WIND CHOP TO PRODUCE 4-5 FT SEAS MONDAY
AND TUESDAY...AFTER BEING 3-4 FT ON SUNDAY.
&&
.TIDES/COASTAL FLOODING...
AS OF 300 PM FRIDAY...ONSHORE WINDS ARE PRODUCING A SMALL 0.5 TO 0.6
FOOT POSITIVE TIDAL ANOMALY AT THE BEACHES. LARGE TIDAL RANGES
ASSOCIATED WITH THE FULL MOON PLUS THIS ANOMALY WILL PUSH WATER
LEVELS TO WITHIN ABOUT 4 INCHES OF MINOR COASTAL FLOODING CRITERIA
AT BOTH WRIGHTSVILLE BEACH AND MYRTLE BEACH THIS EVENING. NO COASTAL
FLOOD ADVISORY IS PLANNED...HOWEVER ALONG THE LOWER CAPE FEAR RIVER
AT DOWNTOWN WILMINGTON WHERE THE OBSERVED ANOMALY IS CLOSER TO +0.8
FEET WE SHOULD ECLIPSE MINOR FLOOD CRITERIA HERE. A COASTAL FLOOD
ADVISORY HAS BEEN ISSUED FOR LOW-LYING AREAS NEAR THE RIVER BETWEEN
8-11 PM.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY FROM 8 PM TO 11 PM EDT THIS EVENING FOR
NCZ107.MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...DRH
LONG TERM...JDW
AVIATION...HDL/TRA
TIDES/COASTAL FLOODING...TRA
AREA FORECAST DISCUSSION
NWS RALEIGH NC
130 PM EDT THU JUL 20 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH FROM THE WEST TODAY...THEN
TRACK SOUTHEAST ACROSS THE CAROLINAS TONIGHT AND SETTLE SOUTH OF THE
AREA ON FRIDAY. MEANWHILE...A WEAK LOW PRESSURE SYSTEM OFF THE
SOUTHEAST COAST WILL TRACK NORTH NORTHEAST OFFSHORE THE CAROLINA
COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...
THE COLD FRONT IS CONTINUING ITS PROGRESSION EASTWARD...NOW LOCATED
ROUGHLY FROM W-CNTRL PA SOUTHWEST ALONG THE APPALACHIANS. THE
CURRENT FORECAST IS STILL ON TRACK...WITH THE FRONT EXPECTED TO MOVE
ACROSS CENTRAL NC FROM LATE THIS AFTERNOON THROUGH THE EVENING.
LATEST HRRR STILL ON TRACK WITH PREV ASSESSMENTS...SUGGESTING WIDELY
SCATTERED PREFRONTAL SHOWERS AND PERHAPS A FEW TSTMS ARE POSSIBLE
THIS AFTERNOON...AND AGAIN THIS EVENING AS THE FRONT PUSHES ACROSS.
NO MAJOR CHANGES TO THE CURRENT FORECAST GRIDS...AND PREV DISC
INCLUDED BELOW FOR REFERENCE.
PREV NEAR TERM AS OF 405 AM THURSDAY...A COLD FRONT...WHICH
CURRENTLY STRETCHES FROM EASTERN CANADA THROUGH THE OHIO VALLEY TO
THE MID-MISSISSIPPI VALLEY REGION...WILL APPROACH FROM THE NORTHWEST
TODAY AS A SHORTWAVE TRAVERSES THE GREAT LAKES ON THE SOUTHERN
PERIPHERY OF AN INTENSE VORTEX NEAR THE HUDSON. THE FRONT IS
GENERALLY EXPECTED TO MOVE INTO THE WESTERN PIEDMONT BY LATE
AFTERNOON...REACHING THE TRIANGLE AREA PRIOR TO MIDNIGHT AND THEN
MOVE INTO THE COASTAL PLAIN EARLY FRIDAY MORNING. AHEAD OF THE
FRONT...CENTRAL NC LIES IN A RELATIVE MIN IN PW...WITH AREAS NEAR 2
INCHES TO OUR NORTH AND SOUTH. STRONG HEATING AND 850MB TEMPS
APPROACHING 20C WILL PUSH TEMPS IN TO THE LOW TO MID 90S TODAY...BUT
INSTABILITY IS PROJECTED TO BE WEAK TODAY...AROUND 500-1000 J/KG
WITH A SLIGHT UPTICK IMMEDIATELY AHEAD OF THE FRONT OWING TO A
NARROW RIBBON OF PREFRONTAL MOISTURE CONVERGENCE. MOST OF THE CAMS
AND LARGER SCALE NWP ARE IN GOOD AGREEMENT ON JUST A BAND OF
SCATTERED CONVECTION REACHING THE TRIAD AROUND 20Z OR SO...THEN
STRUGGLING TO MAINTAIN INTENSITY AND COVERAGE AS IT MOVES EAST IN TO
A LESS SUPPORTIVE ENVIRONMENT AFTER SUNSET. SHEAR PARAMETERS WILL
BE WEAK THROUGHOUT AND WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED.
NOTICEABLY DRIER AIR BEHIND THE FRONT AND CLEARING WILL HELP ALLOW
TEMPS TO FALL INTO THE UPPER 60S IN THE NORTHWEST PIEDMONT..BUT
AREAS TO THE EAST SHOULD STILL SEE LOWS IN THE LOWER 70S AS THE
FRONT SLOWLY PUSHES EAST AND PRECIP CHANCES DWINDLING TOWARD 12Z
FRIDAY.
NOTE...THE WEAK LOW OFF THE GEORGIA COAST ...NOTED BY NHC AS HAVING
ONLY A 10 PERCENT CHANCE OF FURTHER DEVELOPMENT...WILL DRIFT NORTH
TODAY AND BECOME ABSORBED BY THE FRONT OFF THE OBX LATER
TONIGHT...WITH NO DIRECT SENSIBLE IMPACT INLAND.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 405 AM THURSDAY...
THE COLD FRONT WILL PUSH TOWARD THE COAST AND THEN STALL ON FRIDAY
AS A BROAD UPPER TROUGH SLOWLY BEGINS TO DEVELOP OVER THE EASTERN
US. THE NAM AND GFS ARE FAR ENOUGH EAST WITH THE FRONT AND MORE
UNSTABLE AIRMASS TO BE COMPLETELY DRY ON FRIDAY AFTERNOON. THE
ECMWF HANGS THE FRONT UP JUST A TOUCH FURTHER WEST AND DEVELOPS SOME
QPF EAST OF I-95. WILL KEEP A SLIGHT CHANCE OF THE COASTAL
PLAIN...BUT MOST OF THE AREA WILL BE DRY AND MUCH LESS HUMID AS
DEWPOINTS HAVE THE POTENTIAL TO MIX OUT INTO THE UPPER 50S AND LOWER
60S BEHIND THE FRONT. ONLY A SMALL DROP IN THICKNESSES IS
FORECAST...SO HIGHS WILL STILL BE AROUND NORMAL...89-94. LOWS
FRIDAY NIGHT IN THE MID 60S TO AROUND 70.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 1200 PM THURSDAY...
AN UPPER LEVEL RIDGE IS EXPECTED TO PERSIST OVER THE WESTERN CONUS
THROUGH THE EXTENDED PERIOD...WITH THE RIDGE UNDERGOING FURTHER
AMPLIFYING OVER THE ROCKIES BY EARLY NEXT WEEK. DOWNSTREAM IN THE
CAROLINAS AND MID-ATLANTIC...PERSISTING TROUGHING /CYCLONIC FLOW/
ALOFT WILL PREVAIL. THOUGH NUMEROUS SMALL AMPLITUDE DISTURBANCES
/SHORTWAVES/ WILL NO DOUBT BE PRESENT IN THIS AMPLIFIED PATTERN...
THE BULK OF NORTH CAROLINA IS EXPECTED TO REMAIN ALONG/WEST THE BASE
OF THE UPPER LEVEL TROUGH AXIS...WHERE MOISTURE WILL BE LESS
FAVORABLE FOR (OR PERHAPS INSUFFICIENT TO SUPPORT) DIURNAL
CONVECTION...EXCEPT IN EASTERN/COASTAL PORTIONS OF THE CAROLINAS.
WILL MAKE LITTLE CHANGE TO THE PREVIOUS FORECAST INDICATING HIGHS IN
THE LOWER TO MID 90S...LOWS IN THE LOWER 70S...AND DIURNAL PRECIP
CHANCES CONFINED PRIMARILY TO THE SE COASTAL PLAIN. IT SHOULD BE
NOTED THAT A WESTWARD SHIFT IN THE UPPER LEVEL PATTERN (RIDGE/TROUGH
AXES) OVER THE LOWER 48 WOULD RESULT IN INCREASED PRECIP CHANCES
ACROSS PORTIONS OF CENTRAL NC...PARTICULARLY ALONG/EAST OF HWY 1...
THOUGH NO SIGNIFICANT CHANGE IS APPARENT AT THIS TIME. -VINCENT
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 130 PM THURSDAY...
ISOLATED PREFRONTAL SHOWERS AND A FEW TSTMS HAVE DEVELOPED ACROSS
THE WESTERN PIEDMONT...AND MAY PRESENT A BRIEF AVIATION CONCERN THIS
AFTERNOON SHOULD THEY PASS OVER ANY OF THE SITES. IMPACTS WOULD BE
BRIEF PERIOD OF IFR CIGS/VSBY...AND WIND GUSTS AS HIGH AS 30KT. THE
RISK FOR SUCH ACTIVITY WILL SHIFT EAST TOWARD OUR EASTERN TAF SITES
LATER TODAY. OTHERWISE...THE COLD FRONT IS STILL ON TRACK TO MOVE
ACROSS CENTRAL NC LATE THIS EVENING AND OVERNIGHT...SO THE RISK FOR
THE AFOREMENTIONED ISOLATED SHOWERS/TSTMS WILL CONTINUE UNTIL THE
FRONT MOVES THROUGH. LIGHT WINDS WILL SHIFT TO NORTHWESTERLY BEHIND
THE FRONT AS IT SETTLES SOUTH AND EAST OF THE AREA OVERNIGHT. VFR
CONDITIONS ARE EXPECTED BEHIND THE FRONT LATER TONIGHT AND THROUGH
THE REST OF THE 24 HOUR TAF PERIOD.
LOOKING AHEAD: THE COLD FRONT WILL STALL NEAR THE COAST DURING THE
DAYTIME FRIDAY...WITH PREDOMINATELY VFR CONDITIONS EXPECTED THIS
WEEKEND. ITS WORTH NOTING THAT ANY NORTHWARD SHIFT IN THE PATTERN
MAY RESULT IN WORSE CONDITIONS THAN ARE CURRENTLY FORECAST.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...RAH/22
SHORT TERM...22
LONG TERM...VINCENT
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1136 AM EDT THU JUL 20 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH FROM THE WEST TODAY...THEN
TRACK SOUTHEAST ACROSS THE CAROLINAS TONIGHT AND SETTLE SOUTH OF THE
AREA ON FRIDAY. MEANWHILE...A WEAK LOW PRESSURE SYSTEM OFF THE
SOUTHEAST COAST WILL TRACK NORTH NORTHEAST OFFSHORE THE CAROLINA
COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...
THE COLD FRONT IS CONTINUING ITS PROGRESSION EASTWARD...NOW LOCATED
ROUGHLY FROM W-CNTRL PA SOUTHWEST ALONG THE APPALACHIANS. THE
CURRENT FORECAST IS STILL ON TRACK...WITH THE FRONT EXPECTED TO MOVE
ACROSS CENTRAL NC FROM LATE THIS AFTERNOON THROUGH THE EVENING.
LATEST HRRR STILL ON TRACK WITH PREV ASSESSMENTS...SUGGESTING WIDELY
SCATTERED PREFRONTAL SHOWERS AND PERHAPS A FEW TSTMS ARE POSSIBLE
THIS AFTERNOON...AND AGAIN THIS EVENING AS THE FRONT PUSHES ACROSS.
NO MAJOR CHANGES TO THE CURRENT FORECAST GRIDS...AND PREV DISC
INCLUDED BELOW FOR REFERENCE.
PREV NEAR TERM AS OF 405 AM THURSDAY...A COLD FRONT...WHICH
CURRENTLY STRETCHES FROM EASTERN CANADA THROUGH THE OHIO VALLEY TO
THE MID-MISSISSIPPI VALLEY REGION...WILL APPROACH FROM THE NORTHWEST
TODAY AS A SHORTWAVE TRAVERSES THE GREAT LAKES ON THE SOUTHERN
PERIPHERY OF AN INTENSE VORTEX NEAR THE HUDSON. THE FRONT IS
GENERALLY EXPECTED TO MOVE INTO THE WESTERN PIEDMONT BY LATE
AFTERNOON...REACHING THE TRIANGLE AREA PRIOR TO MIDNIGHT AND THEN
MOVE INTO THE COASTAL PLAIN EARLY FRIDAY MORNING. AHEAD OF THE
FRONT...CENTRAL NC LIES IN A RELATIVE MIN IN PW...WITH AREAS NEAR 2
INCHES TO OUR NORTH AND SOUTH. STRONG HEATING AND 850MB TEMPS
APPROACHING 20C WILL PUSH TEMPS IN TO THE LOW TO MID 90S TODAY...BUT
INSTABILITY IS PROJECTED TO BE WEAK TODAY...AROUND 500-1000 J/KG
WITH A SLIGHT UPTICK IMMEDIATELY AHEAD OF THE FRONT OWING TO A
NARROW RIBBON OF PREFRONTAL MOISTURE CONVERGENCE. MOST OF THE CAMS
AND LARGER SCALE NWP ARE IN GOOD AGREEMENT ON JUST A BAND OF
SCATTERED CONVECTION REACHING THE TRIAD AROUND 20Z OR SO...THEN
STRUGGLING TO MAINTAIN INTENSITY AND COVERAGE AS IT MOVES EAST IN TO
A LESS SUPPORTIVE ENVIRONMENT AFTER SUNSET. SHEAR PARAMETERS WILL
BE WEAK THROUGHOUT AND WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED.
NOTICEABLY DRIER AIR BEHIND THE FRONT AND CLEARING WILL HELP ALLOW
TEMPS TO FALL INTO THE UPPER 60S IN THE NORTHWEST PIEDMONT..BUT
AREAS TO THE EAST SHOULD STILL SEE LOWS IN THE LOWER 70S AS THE
FRONT SLOWLY PUSHES EAST AND PRECIP CHANCES DWINDLING TOWARD 12Z
FRIDAY.
NOTE...THE WEAK LOW OFF THE GEORGIA COAST ...NOTED BY NHC AS HAVING
ONLY A 10 PERCENT CHANCE OF FURTHER DEVELOPMENT...WILL DRIFT NORTH
TODAY AND BECOME ABSORBED BY THE FRONT OFF THE OBX LATER
TONIGHT...WITH NO DIRECT SENSIBLE IMPACT INLAND.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 405 AM THURSDAY...
THE COLD FRONT WILL PUSH TOWARD THE COAST AND THEN STALL ON FRIDAY
AS A BROAD UPPER TROUGH SLOWLY BEGINS TO DEVELOP OVER THE EASTERN
US. THE NAM AND GFS ARE FAR ENOUGH EAST WITH THE FRONT AND MORE
UNSTABLE AIRMASS TO BE COMPLETELY DRY ON FRIDAY AFTERNOON. THE
ECMWF HANGS THE FRONT UP JUST A TOUCH FURTHER WEST AND DEVELOPS SOME
QPF EAST OF I-95. WILL KEEP A SLIGHT CHANCE OF THE COASTAL
PLAIN...BUT MOST OF THE AREA WILL BE DRY AND MUCH LESS HUMID AS
DEWPOINTS HAVE THE POTENTIAL TO MIX OUT INTO THE UPPER 50S AND LOWER
60S BEHIND THE FRONT. ONLY A SMALL DROP IN THICKNESSES IS
FORECAST...SO HIGHS WILL STILL BE AROUND NORMAL...89-94. LOWS
FRIDAY NIGHT IN THE MID 60S TO AROUND 70.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 1200 PM THURSDAY...
AN UPPER LEVEL RIDGE IS EXPECTED TO PERSIST OVER THE WESTERN CONUS
THROUGH THE EXTENDED PERIOD...WITH THE RIDGE UNDERGOING FURTHER
AMPLIFYING OVER THE ROCKIES BY EARLY NEXT WEEK. DOWNSTREAM IN THE
CAROLINAS AND MID-ATLANTIC...PERSISTING TROUGHING /CYCLONIC FLOW/
ALOFT WILL PREVAIL. THOUGH NUMEROUS SMALL AMPLITUDE DISTURBANCES
/SHORTWAVES/ WILL NO DOUBT BE PRESENT IN THIS AMPLIFIED PATTERN...
THE BULK OF NORTH CAROLINA IS EXPECTED TO REMAIN ALONG/WEST THE BASE
OF THE UPPER LEVEL TROUGH AXIS...WHERE MOISTURE WILL BE LESS
FAVORABLE FOR (OR PERHAPS INSUFFICIENT TO SUPPORT) DIURNAL
CONVECTION...EXCEPT IN EASTERN/COASTAL PORTIONS OF THE CAROLINAS.
WILL MAKE LITTLE CHANGE TO THE PREVIOUS FORECAST INDICATING HIGHS IN
THE LOWER TO MID 90S...LOWS IN THE LOWER 70S...AND DIURNAL PRECIP
CHANCES CONFINED PRIMARILY TO THE SE COASTAL PLAIN. IT SHOULD BE
NOTED THAT A WESTWARD SHIFT IN THE UPPER LEVEL PATTERN (RIDGE/TROUGH
AXES) OVER THE LOWER 48 WOULD RESULT IN INCREASED PRECIP CHANCES
ACROSS PORTIONS OF CENTRAL NC...PARTICULARLY ALONG/EAST OF HWY 1...
THOUGH NO SIGNIFICANT CHANGE IS APPARENT AT THIS TIME. -VINCENT
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 645 AM THURSDAY...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND CROSS THE
AREA LATE THIS EVENING AND TONIGHT. INSTABILITY IS EXPECTED TO BE
LIMITED WHEN THE FRONT ARRIVES...ESPECIALLY TONIGHT AS THE FRONT
MOVES EAST ACROSS CENTRAL NC. SCATTERED SHOWERS AND A FEW ISOLATED
STORMS WILL BE POSSIBLE ALONG THE FRONT...FIRST AROUND KINT/KGSO
AFTER 21Z AND THEN KRDU/KRWI/KFAY IN THE 00Z TO 06Z TIME FRAME.
WHILE WIDESPREAD ADVERSE AVIATION CONDITIONS ARE NOT EXPECTED...A
HEAVY DOWNPOUR AND BRIEF PERIOD OF SUB-VFR CONDITIONS IS POSSIBLE AT
AT TAF SITE. LIGHT WINDS WILL SHIFT TO NORTHWESTERLY BEHIND THE
FRONT AS IT SETTLES SOUTH AND EAST OF THE AREA.
LOOKING AHEAD: THE COLD FRONT WILL STALL NEAR THE COAST ON
FRIDAY...WITH PREDOMINATELY VFR CONDITIONS EXPECTED THIS WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...RAH/22
SHORT TERM...22
LONG TERM...VINCENT
AVIATION...22
AREA FORECAST DISCUSSION...CORRECTED
NWS RALEIGH NC
1100 AM EDT THU JUL 20 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH FROM THE WEST TODAY...THEN
TRACK SOUTHEAST ACROSS THE CAROLINAS TONIGHT AND SETTLE SOUTH OF THE
AREA ON FRIDAY. MEANWHILE...A WEAK LOW PRESSURE SYSTEM OFF THE
SOUTHEAST COAST WILL TRACK NORTH NORTHEAST OFFSHORE THE CAROLINA
COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 AM THURSDAY...
THE COLD FRONT IS CONTINUING ITS PROGRESSION EASTWARD...NOW LOCATED
ROUGHLY FROM W-CNTRL PA SOUTHWEST ALONG THE APPALACHIANS. THE
CURRENT FORECAST IS STILL ON TRACK...WITH THE FRONT EXPECTED TO MOVE
ACROSS CENTRAL NC FROM LATE THIS AFTERNOON THROUGH THE EVENING.
LATEST HRRR STILL ON TRACK WITH PREV ASSESSMENTS...SUGGESTING WIDELY
SCATTERED PREFRONTAL SHOWERS AND PERHAPS A FEW TSTMS ARE POSSIBLE
THIS AFTERNOON...AND AGAIN THIS EVENING AS THE FRONT PUSHES ACROSS.
NO MAJOR CHANGES TO THE CURRENT FORECAST GRIDS...AND PREV DISC
INCLUDED BELOW FOR REFERENCE.
PREV NEAR TERM AS OF 405 AM THURSDAY...A COLD FRONT...WHICH
CURRENTLY STRETCHES FROM EASTERN CANADA THROUGH THE OHIO VALLEY TO
THE MID-MISSISSIPPI VALLEY REGION...WILL APPROACH FROM THE NORTHWEST
TODAY AS A SHORTWAVE TRAVERSES THE GREAT LAKES ON THE SOUTHERN
PERIPHERY OF AN INTENSE VORTEX NEAR THE HUDSON. THE FRONT IS
GENERALLY EXPECTED TO MOVE INTO THE WESTERN PIEDMONT BY LATE
AFTERNOON...REACHING THE TRIANGLE AREA PRIOR TO MIDNIGHT AND THEN
MOVE INTO THE COASTAL PLAIN EARLY FRIDAY MORNING. AHEAD OF THE
FRONT...CENTRAL NC LIES IN A RELATIVE MIN IN PW...WITH AREAS NEAR 2
INCHES TO OUR NORTH AND SOUTH. STRONG HEATING AND 850MB TEMPS
APPROACHING 20C WILL PUSH TEMPS IN TO THE LOW TO MID 90S TODAY...BUT
INSTABILITY IS PROJECTED TO BE WEAK TODAY...AROUND 500-1000 J/KG
WITH A SLIGHT UPTICK IMMEDIATELY AHEAD OF THE FRONT OWING TO A
NARROW RIBBON OF PREFRONTAL MOISTURE CONVERGENCE. MOST OF THE CAMS
AND LARGER SCALE NWP ARE IN GOOD AGREEMENT ON JUST A BAND OF
SCATTERED CONVECTION REACHING THE TRIAD AROUND 20Z OR SO...THEN
STRUGGLING TO MAINTAIN INTENSITY AND COVERAGE AS IT MOVES EAST IN TO
A LESS SUPPORTIVE ENVIRONMENT AFTER SUNSET. SHEAR PARAMETERS WILL
BE WEAK THROUGHOUT AND WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED.
NOTICEABLY DRIER AIR BEHIND THE FRONT AND CLEARING WILL HELP ALLOW
TEMPS TO FALL INTO THE UPPER 60S IN THE NORTHWEST PIEDMONT..BUT
AREAS TO THE EAST SHOULD STILL SEE LOWS IN THE LOWER 70S AS THE
FRONT SLOWLY PUSHES EAST AND PRECIP CHANCES DWINDLING TOWARD 12Z
FRIDAY.
NOTE...THE WEAK LOW OFF THE GEORGIA COAST ...NOTED BY NHC AS HAVING
ONLY A 10 PERCENT CHANCE OF FURTHER DEVELOPMENT...WILL DRIFT NORTH
TODAY AND BECOME ABSORBED BY THE FRONT OFF THE OBX LATER
TONIGHT...WITH NO DIRECT SENSIBLE IMPACT INLAND.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 405 AM THURSDAY...
THE COLD FRONT WILL PUSH TOWARD THE COAST AND THEN STALL ON FRIDAY
AS A BROAD UPPER TROUGH SLOWLY BEGINS TO DEVELOP OVER THE EASTERN
US. THE NAM AND GFS ARE FAR ENOUGH EAST WITH THE FRONT AND MORE
UNSTABLE AIRMASS TO BE COMPLETELY DRY ON FRIDAY AFTERNOON. THE
ECMWF HANGS THE FRONT UP JUST A TOUCH FURTHER WEST AND DEVELOPS SOME
QPF EAST OF I-95. WILL KEEP A SLIGHT CHANCE OF THE COASTAL
PLAIN...BUT MOST OF THE AREA WILL BE DRY AND MUCH LESS HUMID AS
DEWPOINTS HAVE THE POTENTIAL TO MIX OUT INTO THE UPPER 50S AND LOWER
60S BEHIND THE FRONT. ONLY A SMALL DROP IN THICKNESSES IS
FORECAST...SO HIGHS WILL STILL BE AROUND NORMAL...89-94. LOWS
FRIDAY NIGHT IN THE MID 60S TO AROUND 70.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 405 AM THURSDAY...
THE MODELS GENERALLY AGREE THAT A RELATIVELY AMPLIFIED FLOW
PATTERN...ONE CHARACTERIZED BY A STRONG RIDGE CENTERED OVER THE
SOUTHWESTERN US AND DOWNSTREAM A BROAD TROUGH EAST OF THE
ROCKIES...WILL PERSIST THROUGH THE MEDIUM RANGE...THOUGH WITH
INDICATION FROM THE ENSEMBLE MEANS OF SOME RELAXATION OF THE
FLOW/TOWARD LESS AMPLIFIED-MORE ZONAL LATE NEXT WEEK.
DESPITE THE PRESENCE OF A TROUGH AND CYCLONIC FLOW ALOFT OVER THE
EASTERN US...UNSEASONABLY DRY AIR WILL HAVE SPREAD IN THE LEE OF THE
APPALACHIANS...BEHIND A LEAD FRONTAL ZONE FORECAST TO CROSS THE RAH
FORECAST AREA LATER TONIGHT. THIS BOUNDARY WILL EFFECTIVELY PIN RICH
MOISTURE ALONG COASTAL AREAS...WITH MUCH DRIER AIR...PARTICULARLY
WITH DIURNAL HEATING/BL MIXING WESTWARD ACROSS CENTRAL NC. THIS
DRIER AIR WILL SIGNIFICANTLY HINDER THE DEVELOPMENT OF ANY
APPRECIABLE CAPE AND PRECIPITATION CHANCES THROUGHOUT THE FORECAST
PERIOD...WITH THE RELATIVELY HIGHER CHANCES/~25 PERCENT ALONG AND
EAST OF A PIEDMONT TROUGH EACH LATE AFTERNOON-EARLY EVENING.
ANY EVEN WEAK STORM WRT REFLECTIVITY...HOWEVER...WOULD POSE A RISK OF
STRONG...EVAPORATIVELY-COOLED DOWNBURST WINDS IN AN ENVIRONMENT
CHARACTERIZED BY STEEP/NEAR DRY ADIABATIC LOW LEVEL LAPSE RATES AND
LARGE/~30-35 DEGREE SURFACE DEWPOINT DEPRESSIONS...DRIVEN BY A
COMBINATION OF THE AFOREMENTIONED MIXING OUT OF AN ALREADY
CONTINENTAL AIR MASS...AND HOT SURFACE TEMPERATURES IN THE LOWER TO
MIDDLE 90S.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 645 AM THURSDAY...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND CROSS THE
AREA LATE THIS EVENING AND TONIGHT. INSTABILITY IS EXPECTED TO BE
LIMITED WHEN THE FRONT ARRIVES...ESPECIALLY TONIGHT AS THE FRONT
MOVES EAST ACROSS CENTRAL NC. SCATTERED SHOWERS AND A FEW ISOLATED
STORMS WILL BE POSSIBLE ALONG THE FRONT...FIRST AROUND KINT/KGSO
AFTER 21Z AND THEN KRDU/KRWI/KFAY IN THE 00Z TO 06Z TIME FRAME.
WHILE WIDESPREAD ADVERSE AVIATION CONDITIONS ARE NOT EXPECTED...A
HEAVY DOWNPOUR AND BRIEF PERIOD OF SUB-VFR CONDITIONS IS POSSIBLE AT
AT TAF SITE. LIGHT WINDS WILL SHIFT TO NORTHWESTERLY BEHIND THE
FRONT AS IT SETTLES SOUTH AND EAST OF THE AREA.
LOOKING AHEAD: THE COLD FRONT WILL STALL NEAR THE COAST ON
FRIDAY...WITH PREDOMINATELY VFR CONDITIONS EXPECTED THIS WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
CORRECTED ISSUE TIME
SYNOPSIS...22
NEAR TERM...RAH/22
SHORT TERM...22
LONG TERM...26
AVIATION...22
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1000 AM EDT THU JUL 20 2015
.SYNOPSIS...A COLD FRONT WILL APPROACH FROM THE WEST TODAY...THEN
TRACK SOUTHEAST ACROSS THE CAROLINAS TONIGHT AND SETTLE SOUTH OF THE
AREA ON FRIDAY. MEANWHILE...A WEAK LOW PRESSURE SYSTEM OFF THE
SOUTHEAST COAST WILL TRACK NORTH NORTHEAST OFFSHORE THE CAROLINA
COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM THURSDAY...
THE COLD FRONT IS CONTINUING ITS PROGRESSION EASTWARD...NOW LOCATED
ROUGHLY FROM W-CNTRL PA SOUTHWEST ALONG THE APPALACHIANS. THE
CURRENT FORECAST IS STILL ON TRACK...WITH THE FRONT EXPECTED TO MOVE
ACROSS CENTRAL NC FROM LATE THIS AFTERNOON THROUGH THE EVENING.
LATEST HRRR STILL ON TRACK WITH PREV ASSESSMENTS...SUGGESTING WIDELY
SCATTERED PREFRONTAL SHOWERS AND PERHAPS A FEW TSTMS ARE POSSIBLE
THIS AFTERNOON...AND AGAIN THIS EVENING AS THE FRONT PUSHES ACROSS.
NO MAJOR CHANGES TO THE CURRENT FORECAST GRIDS...AND PREV DISC
INCLUDED BELOW FOR REFERENCE.
PREV NEAR TERM AS OF 405 AM THURSDAY...A COLD FRONT...WHICH
CURRENTLY STRETCHES FROM EASTERN CANADA THROUGH THE OHIO VALLEY TO
THE MID-MISSISSIPPI VALLEY REGION...WILL APPROACH FROM THE NORTHWEST
TODAY AS A SHORTWAVE TRAVERSES THE GREAT LAKES ON THE SOUTHERN
PERIPHERY OF AN INTENSE VORTEX NEAR THE HUDSON. THE FRONT IS
GENERALLY EXPECTED TO MOVE INTO THE WESTERN PIEDMONT BY LATE
AFTERNOON...REACHING THE TRIANGLE AREA PRIOR TO MIDNIGHT AND THEN
MOVE INTO THE COASTAL PLAIN EARLY FRIDAY MORNING. AHEAD OF THE
FRONT...CENTRAL NC LIES IN A RELATIVE MIN IN PW...WITH AREAS NEAR 2
INCHES TO OUR NORTH AND SOUTH. STRONG HEATING AND 850MB TEMPS
APPROACHING 20C WILL PUSH TEMPS IN TO THE LOW TO MID 90S TODAY...BUT
INSTABILITY IS PROJECTED TO BE WEAK TODAY...AROUND 500-1000 J/KG
WITH A SLIGHT UPTICK IMMEDIATELY AHEAD OF THE FRONT OWING TO A
NARROW RIBBON OF PREFRONTAL MOISTURE CONVERGENCE. MOST OF THE CAMS
AND LARGER SCALE NWP ARE IN GOOD AGREEMENT ON JUST A BAND OF
SCATTERED CONVECTION REACHING THE TRIAD AROUND 20Z OR SO...THEN
STRUGGLING TO MAINTAIN INTENSITY AND COVERAGE AS IT MOVES EAST IN TO
A LESS SUPPORTIVE ENVIRONMENT AFTER SUNSET. SHEAR PARAMETERS WILL
BE WEAK THROUGHOUT AND WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED.
NOTICEABLY DRIER AIR BEHIND THE FRONT AND CLEARING WILL HELP ALLOW
TEMPS TO FALL INTO THE UPPER 60S IN THE NORTHWEST PIEDMONT..BUT
AREAS TO THE EAST SHOULD STILL SEE LOWS IN THE LOWER 70S AS THE
FRONT SLOWLY PUSHES EAST AND PRECIP CHANCES DWINDLING TOWARD 12Z
FRIDAY.
NOTE...THE WEAK LOW OFF THE GEORGIA COAST ...NOTED BY NHC AS HAVING
ONLY A 10 PERCENT CHANCE OF FURTHER DEVELOPMENT...WILL DRIFT NORTH
TODAY AND BECOME ABSORBED BY THE FRONT OFF THE OBX LATER
TONIGHT...WITH NO DIRECT SENSIBLE IMPACT INLAND.
&&
.SHORT TERM /FRIDAY AND FRIDAY NIGHT/...
AS OF 405 AM THURSDAY...
THE COLD FRONT WILL PUSH TOWARD THE COAST AND THEN STALL ON FRIDAY
AS A BROAD UPPER TROUGH SLOWLY BEGINS TO DEVELOP OVER THE EASTERN
US. THE NAM AND GFS ARE FAR ENOUGH EAST WITH THE FRONT AND MORE
UNSTABLE AIRMASS TO BE COMPLETELY DRY ON FRIDAY AFTERNOON. THE
ECMWF HANGS THE FRONT UP JUST A TOUCH FURTHER WEST AND DEVELOPS SOME
QPF EAST OF I-95. WILL KEEP A SLIGHT CHANCE OF THE COASTAL
PLAIN...BUT MOST OF THE AREA WILL BE DRY AND MUCH LESS HUMID AS
DEWPOINTS HAVE THE POTENTIAL TO MIX OUT INTO THE UPPER 50S AND LOWER
60S BEHIND THE FRONT. ONLY A SMALL DROP IN THICKNESSES IS
FORECAST...SO HIGHS WILL STILL BE AROUND NORMAL...89-94. LOWS
FRIDAY NIGHT IN THE MID 60S TO AROUND 70.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 405 AM THURSDAY...
THE MODELS GENERALLY AGREE THAT A RELATIVELY AMPLIFIED FLOW
PATTERN...ONE CHARACTERIZED BY A STRONG RIDGE CENTERED OVER THE
SOUTHWESTERN US AND DOWNSTREAM A BROAD TROUGH EAST OF THE
ROCKIES...WILL PERSIST THROUGH THE MEDIUM RANGE...THOUGH WITH
INDICATION FROM THE ENSEMBLE MEANS OF SOME RELAXATION OF THE
FLOW/TOWARD LESS AMPLIFIED-MORE ZONAL LATE NEXT WEEK.
DESPITE THE PRESENCE OF A TROUGH AND CYCLONIC FLOW ALOFT OVER THE
EASTERN US...UNSEASONABLY DRY AIR WILL HAVE SPREAD IN THE LEE OF THE
APPALACHIANS...BEHIND A LEAD FRONTAL ZONE FORECAST TO CROSS THE RAH
FORECAST AREA LATER TONIGHT. THIS BOUNDARY WILL EFFECTIVELY PIN RICH
MOISTURE ALONG COASTAL AREAS...WITH MUCH DRIER AIR...PARTICULARLY
WITH DIURNAL HEATING/BL MIXING WESTWARD ACROSS CENTRAL NC. THIS
DRIER AIR WILL SIGNIFICANTLY HINDER THE DEVELOPMENT OF ANY
APPRECIABLE CAPE AND PRECIPITATION CHANCES THROUGHOUT THE FORECAST
PERIOD...WITH THE RELATIVELY HIGHER CHANCES/~25 PERCENT ALONG AND
EAST OF A PIEDMONT TROUGH EACH LATE AFTERNOON-EARLY EVENING.
ANY EVEN WEAK STORM WRT REFLECTIVITY...HOWEVER...WOULD POSE A RISK OF
STRONG...EVAPORATIVELY-COOLED DOWNBURST WINDS IN AN ENVIRONMENT
CHARACTERIZED BY STEEP/NEAR DRY ADIABATIC LOW LEVEL LAPSE RATES AND
LARGE/~30-35 DEGREE SURFACE DEWPOINT DEPRESSIONS...DRIVEN BY A
COMBINATION OF THE AFOREMENTIONED MIXING OUT OF AN ALREADY
CONTINENTAL AIR MASS...AND HOT SURFACE TEMPERATURES IN THE LOWER TO
MIDDLE 90S.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 645 AM THURSDAY...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND CROSS THE
AREA LATE THIS EVENING AND TONIGHT. INSTABILITY IS EXPECTED TO BE
LIMITED WHEN THE FRONT ARRIVES...ESPECIALLY TONIGHT AS THE FRONT
MOVES EAST ACROSS CENTRAL NC. SCATTERED SHOWERS AND A FEW ISOLATED
STORMS WILL BE POSSIBLE ALONG THE FRONT...FIRST AROUND KINT/KGSO
AFTER 21Z AND THEN KRDU/KRWI/KFAY IN THE 00Z TO 06Z TIME FRAME.
WHILE WIDESPREAD ADVERSE AVIATION CONDITIONS ARE NOT EXPECTED...A
HEAVY DOWNPOUR AND BRIEF PERIOD OF SUB-VFR CONDITIONS IS POSSIBLE AT
AT TAF SITE. LIGHT WINDS WILL SHIFT TO NORTHWESTERLY BEHIND THE
FRONT AS IT SETTLES SOUTH AND EAST OF THE AREA.
LOOKING AHEAD: THE COLD FRONT WILL STALL NEAR THE COAST ON
FRIDAY...WITH PREDOMINATELY VFR CONDITIONS EXPECTED THIS WEEKEND.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...22
NEAR TERM...RAH/22
SHORT TERM...22
LONG TERM...26
AVIATION...22
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1136 PM CDT WED JUL 29 2015
.UPDATE...
ISSUED AT 1131 PM CDT WED JUL 29 2015
WEAK SHORT WAVE OVER S CENTRAL SASK GENERATING A FEW TSRA. CURRENT
SPC HRRR PROPAGATES CONVECTION ESE OVERNIGHT AND GENERALLY
DISSIPATES ANY PCPN BEFORE GETTING TOO FAR INTO THE FAR NW PORTION
OF OUR FA AROUND 12Z. KEPT FORECAST DRY THIS AREA BUT WORTH
MONITORING.
UPDATE ISSUED AT 949 PM CDT WED JUL 29 2015
NO CHANGES NECESSARY.
UPDATE ISSUED AT 639 PM CDT WED JUL 29 2015
HAVE CANCELLED WIND ADVISORY AS WINDS HAVE DROPPED BELOW ADVISORY
THRESHOLDS AND WILL CONTINUE TO DO SO THROUGH THE EVENING.
OTHERWISE NO CHANGES TO CURRENT FORECAST.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 256 PM CDT WED JUL 29 2015
FORECAST CHALLENGE WILL BE HOW FAST THE GUSTY NORTHWEST WINDS DIE
OFF THIS EVENING...THEN TURNS TO THE POTENTIAL FOR ANY AFTERNOON
CONVECTION THE NEXT FEW DAYS. AS FOR THIS AFTERNOON...WINDS WERE
STILL QUITE GUSTY EVERYWHERE BUT THE STRONGEST WINDS WERE ACROSS
THE NORTHERN FA. CURRENT WIND ADVISORY SET TO EXPIRE AT 7 PM AND
WILL LET THAT RIDE AS IS. SOME CUMULUS DID FORM THIS AFTERNOON BUT
IT SHOULD THIN OUT AGAIN THIS EVENING. PATTERN IS PRETTY SIMILAR
THE NEXT THREE DAYS WITH NORTHWEST FLOW ALOFT. EACH OF THESE DAYS
THE MODELS SHOW WEAK WAVES DROPPING THRU POTENTIALLY DURING PEAK
HEATING...WHICH COULD SET OFF A FEW SHOWERS OR TSTMS. FOR THU
AFTERNOON THIS WOULD POTENTIALLY BE AROUND THE LAKE OF THE WOODS.
WENT AHEAD AND MATCHED KDLH WITH SOME ISOLATED CHANCES FOR
SHOWERS/TSTMS...ALTHOUGH CONFIDENCE IS QUITE LOW.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 256 PM CDT WED JUL 29 2015
SAME STORY GOES FOR FRI...WITH THE POTENTIAL AREA STILL BEING
AROUND THE LAKE OF THE WOODS. CONFIDENCE ALSO LOW SO DID NOT
MENTION AT THIS POINT. FOR SAT MODELS ALL OVER THE PLACE BUT
CONSISTENT IN MINIMAL IF ANY PCPN. BROADBRUSHED AN ISOLATED
MENTION BUT AGAIN CONFIDENCE LOW.
FOR SUNDAY-WEDNESDAY...MODELS IN AGREEMENT DEPICTING NORTHWEST
FLOW ALOFT. MUCH OF THIS PERIOD SHOULD BE DRY WITH SFC HIGH
PRESSURE IN CONTROL...ALTHOUGH HARD TO FORECAST WEAK WAVES WITH
THIS UPPER FLOW PATTERN. AT ANY RATE...NOT EXPECTING ANY
SIGNIFICANT WEATHER. TEMPERATURES GENERALLY NEAR NORMAL VALUES. BY
THE MIDDLE OR END OF NEXT WEEK THERE IS POTENTIAL TO GET BACK INTO
ZONAL/SW FLOW ALOFT...ALTHOUGH CONFIDENCE IN THIS POTENTIAL
PATTERN CHANGE IS STILL LOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1131 PM CDT WED JUL 29 2015
MAY SEE SOME BRIEF MID LEVEL CIGS ACROSS DVL-GFK ASSOCIATED WITH
WEAKENING SHORT WAVE CURRENTLY OVER S CENTRAL SASK OTHERWISE NO
CIGS ANTICIPATED. WINDS WILL INCREASE IN THE AM BUT NOT NEAR AS
STRONG AS LAST TWO DAYS.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...VOELKER
SHORT TERM...GODON
LONG TERM...GODON/TG
AVIATION...VOELKER
AREA FORECAST DISCUSSION
NWS NORMAN OK
1222 PM CDT THU JUL 30 2015
.UPDATE...
WE HAVE BEEN UPDATING THE FORECAST THROUGH THE MORNING WITH RADAR
AND MESOSCALE MODEL TRENDS. JUST MADE ANOTHER BIG UPDATE FOR NOT
ONLY EXPECTED AFTERNOON POPS... BUT ALSO SIGNIFICANTLY LOWER
FORECAST MAX TEMPS ACROSS NORTHERN OKLAHOMA WHERE CLOUDS AND
PRECIPITATION WILL NOT ALLOW THE POST-FRONTAL AIR TO WARM MUCH
THIS AFTERNOON. GENERALLY POPULATED WITH HOURLY RAP TEMPERATURES
ALTHOUGH DID NOT BRING TEMPS QUITE AS HOT IN THE SOUTH AS RAP.
&&
.PREV DISCUSSION... /ISSUED 609 AM CDT THU JUL 30 2015/
AVIATION...
12Z TAFS... SHOWERS/STORMS WILL BE POSSIBLE IN PARTS OF NORTHERN
OK THIS MORNING. ADDITIONAL ISOLATED TO SCATTERED SHOWERS/STORMS
WILL BE POSSIBLE THIS AFTERNOON AND TONIGHT ACROSS PARTS OF THE
AREA. CHANCES ARE TOO LOW IN SOME AREAS OR AT TIMES FOR A MENTION
IN TAFS. GUSTY VARIABLE WINDS WILL BE POSSIBLE NEAR THE STORMS.
MOSTLY MVFR AND VFR CEILINGS ARE EXPECTED THROUGH THE TAF PERIOD.
PREV DISCUSSION... /ISSUED 345 AM CDT THU JUL 30 2015/
DISCUSSION...
SCATTERED SHOWERS/STORMS ARE BEGINNING TO DEVELOP SOUTHWEST FROM A
CLUSTER OF STORMS IN S KS ACROSS THE PANHANDLES TOWARDS A LARGER
AREA OF STORMS IN EASTERN NM EARLY THIS MORNING. THIS ACTIVITY COULD
EVENTUALLY MOVE/DEVELOP INTO PORTIONS OF THE FA THIS MORNING.
ADDITIONAL ISOLATED TO SCATTERED STORMS WILL BE POSSIBLE THIS
AFTERNOON WITH THE FRONTAL BOUNDARY AND ANY LINGERING OUTFLOW
BOUNDARIES ACROSS THE FA BEING FOCI. THE BEST CHANCE MAY ACTUALLY BE
IN CENTRAL AND/OR SOUTHERN SECTIONS OF THE FA WHERE LESS CLOUD COVER
IS EXPECTED SO MORE SFC HEATING WOULD LIKELY OCCUR.
MODELS STILL SHOW THE CENTER OF THE UPPER HIGH SLOWLY MOVING WEST
WITH NW FLOW POSSIBLY DEVELOPING OVER PORTIONS OF THE FA AND MID-
LEVEL DISTURBANCES MOVING THROUGH THE FLOW. SHOWERS AND
THUNDERSTORMS WILL REMAIN POSSIBLE ACROSS PARTS OF THE FA AT LEAST
THROUGH THE WEEKEND AND POSSIBLY INTO EARLY NEXT WEEK. THE GFS SHOWS
THE UPPER HIGH TRYING TO BUILD BACK TO THE EAST INTO THE REGION THE
MIDDLE OF NEXT WEEK ALTHOUGH THE HIGH PRESSURE CENTER REMAINS TO THE
WEST AND THE RIDGE IS NOT AS STRONG AS HAS THE PAST WEEK. MEANWHILE
THE ECMWF HOLDS THE CENTER OF THE HIGH FURTHER WEST/SOUTHWEST AND
MAINTAINS SOMEWHAT OF A NW FLOW OVER THE REGION THROUGH NEXT WEEK.
IF THE GFS IS RIGHT THE CHANCES FOR RAIN WOULD BE LESSER THAN THE
ECMWF THROUGH NEXT WEEK BUT NEITHER IS ZERO FOR ANY LONG PERIOD OF
TIME AS DISTURBANCES CONTINUE TO MOVE THROUGH THE FLOW.
HOT AND HUMID CONDITIONS WILL OCCUR AGAIN TODAY ACROSS PARTS OF THE
FA. TRIPLE DIGIT HEAT INDICES WILL BE LIKELY IN SOUTHERN OKLAHOMA
AND WESTERN NORTH TEXAS. A FEW PLACES IN SE PARTS OF THE FA COULD
REACH 105 HEAT INDEX VALUES BUT THIS IS A BIT UNCERTAIN SO WILL
LEAVE FOR THE DAY SHIFT TO KEEP AND EYE ON AND NOT ISSUE A HEAT
ADVISORY AT THIS TIME. TEMPS WILL REMAIN SLIGHTLY COOLER /80S TO LOW
90S/ THROUGH THE WEEKEND BEFORE WARMING BACK INTO THE MID AND UPPER
90S NEXT WEEK. THIS WILL LIKELY LEAD TO A RETURN OF THE TRIPLE DIGIT
HEAT INDICES FOR AT LEAST PARTS OF THE FA NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 95 72 87 71 / 30 30 30 10
HOBART OK 96 72 90 71 / 40 30 30 30
WICHITA FALLS TX 100 76 95 73 / 20 20 30 20
GAGE OK 81 68 87 67 / 80 30 30 20
PONCA CITY OK 89 69 89 70 / 80 20 20 10
DURANT OK 101 75 93 73 / 20 30 30 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION...UPDATED
NWS TULSA OK
1207 PM CDT THU JUL 30 2015
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
FOR THE 18Z TAFS... VFR CONDITIONS WILL PREVAIL AT ALL SITES
THROUGHOUT THE 24 HOUR FORECAST PERIOD. THUNDERSTORM CHANCES WILL
INCREASE ACROSS THE AREA THIS AFTERNOON AND OVERNIGHT. HOWEVER...
OVERALL LOW CHANCES AND EXPECTED LOW COVERAGE WILL PRECLUDE
MENTIONING IN ANY PARTICULAR TAF.
&&
.PREV DISCUSSION... /ISSUED 1051 AM CDT THU JUL 30 2015/
..UPDATE...
DISCUSSION...
THUNDERSTORMS MADE A RUN AT THE NORTHWESTERN PORTION OF THE
FORECAST AREA THIS MORNING. WE RAISED POPS IN REACTION TO THIS
FROM ABOUT TULSA NORTHWESTWARD. CURRENTLY... EASTWARD PROGRESSION
OF PRECIP SEEMS TO BE COMING TO A HALT... IN AGREEMENT WITH THE
HRRR AND RUC MODELS. CLOUD TOPS ARE WARMING RAPIDLY ON THE
EASTERN SIDE OF THE PRECIP SHIELD AS WELL... CONFIRMING THAT THE
THUNDERSTORM ACTIVITY HAS JUST ABOUT REACHED ITS EASTWARD LIMIT.
THAT SAID... AN OUTFLOW BOUNDARY IS RACING EASTWARD ACROSS OSAGE
AND PAWNEE COUNTIES... WHICH MAY BE ENOUGH TO INIATE ISOLATED
CONVECTIVE ACTIVITY. THIS WILL JUSTIFY LEAVING THE HIGHER POPS IN
FOR THE NEXT FEW HOURS. UPDATED PRODUCTS HAVE BEEN SENT.
PREV DISCUSSION... /ISSUED 634 AM CDT THU JUL 30 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
MOIST AND UNSTABLE AIR MASS ACROSS THE REGION ALONG WITH A WEAK COLD
FRONT IN THE PROXIMITY WILL SUPPORT SCATTERED TSRA THROUGH TONIGHT.
ACTIVITY IN SOUTH CENTRAL KS MAY IMPACT BVO/TUL/RVS LATER THIS
MORNING. BEST CHANCES SHOULD BE AT NERN OK SITES THIS AFTERNOON AND
MLC/FSM AFTER 00Z. ALTHOUGH LAYERED CLOUDS WILL BE THE RULE FOR MUCH
OF THIS FORECAST PERIOD...VFR CONDITIONS SHOULD PREVAIL OUTSIDE OF
TSRA...WHICH WILL REDUCE VSBY TO MVFR.
PREV DISCUSSION... /ISSUED 259 AM CDT THU JUL 30 2015/
DISCUSSION...
WEAK SFC BOUNDARY HAS PUSHED WELL INTO ERN OK THIS MORNING. THIS
FEATURE WILL SERVE AS FOCUS FOR WIDELY SCATTERED TO SCATTERED
CONVECTION TOMORROW AND INTO FRIDAY...ESPECIALLY OVER ERN OK. HEAT
ADVISORY CRITERIA WILL BE FLIRTED WITH ACROSS PARTS OF EAST
CENTRAL AND SOUTHEAST OKLAHOMA. WILL FOREGO AN ADVISORY AT THIS
TIME GIVEN MARGINAL VALUES EXPECTED ALONG WITH THE SHORT DURATION.
MODELS HAVE REMAINED FAIRLY CONSISTENT IN PUSHING THE BOUNDARY
FURTHER WEST BY LATER IN THE DAY FRIDAY...WITH MOST CONVECTION
ACROSS CENTRAL AN WESTERN SECTIONS OF OKLAHOMA. UPPER HIGH TO
REMAINED POSITIONED TO THE WEST OF THE FA THROUGH THE FORECAST
PERIOD...WITH SOME HEIGHT RISES NOTED THROUGH THE WEEKEND PER THE
GFS. LATER IN THE FORECAST CYCLE...ECMWF FLATTENS THE RIDGE AS AS
WAVE TRAVERSES THE CENTRAL PLAINS...WHILE THE GFS MAINTAINS
HIGHER HEIGHTS/WEAK NW FLOW. WILL KEEP FORECAST DRY FOR NOW BEYOND
FRIDAY. TEMPERATURES WILL INCREASE SOME OVER THE WEEKEND...BUT
WILL LIKELY NOT BE AS HOT AS OBSERVED THE LAST WEEK GIVEN THE
POSITIONING OF THE UPPER RIDGE TO THE WEST.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...06
AREA FORECAST DISCUSSION
NWS TULSA OK
1051 AM CDT THU JUL 30 2015
...UPDATE...
.DISCUSSION...
THUNDERSTORMS MADE A RUN AT THE NORTHWESTERN PORTION OF THE
FORECAST AREA THIS MORNING. WE RAISED POPS IN REACTION TO THIS
FROM ABOUT TULSA NORTHWESTWARD. CURRENTLY... EASTWARD PROGRESSION
OF PRECIP SEEMS TO BE COMING TO A HALT... IN AGREEMENT WITH THE
HRRR AND RUC MODELS. CLOUD TOPS ARE WARMING RAPIDLY ON THE
EASTERN SIDE OF THE PRECIP SHIELD AS WELL... CONFIRMING THAT THE
THUNDERSTORM ACTIVITY HAS JUST ABOUT REACHED ITS EASTWARD LIMIT.
THAT SAID... AN OUTFLOW BOUNDARY IS RACING EASTWARD ACROSS OSAGE
AND PAWNEE COUNTIES... WHICH MAY BE ENOUGH TO INIATE ISOLATED
CONVECTIVE ACTIVITY. THIS WILL JUSTIFY LEAVING THE HIGHER POPS IN
FOR THE NEXT FEW HOURS. UPDATED PRODUCTS HAVE BEEN SENT.
&&
.PREV DISCUSSION... /ISSUED 634 AM CDT THU JUL 30 2015/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG.
MOIST AND UNSTABLE AIR MASS ACROSS THE REGION ALONG WITH A WEAK COLD
FRONT IN THE PROXIMITY WILL SUPPORT SCATTERED TSRA THROUGH TONIGHT.
ACTIVITY IN SOUTH CENTRAL KS MAY IMPACT BVO/TUL/RVS LATER THIS
MORNING. BEST CHANCES SHOULD BE AT NERN OK SITES THIS AFTERNOON AND
MLC/FSM AFTER 00Z. ALTHOUGH LAYERED CLOUDS WILL BE THE RULE FOR MUCH
OF THIS FORECAST PERIOD...VFR CONDITIONS SHOULD PREVAIL OUTSIDE OF
TSRA...WHICH WILL REDUCE VSBY TO MVFR.
PREV DISCUSSION... /ISSUED 259 AM CDT THU JUL 30 2015/
DISCUSSION...
WEAK SFC BOUNDARY HAS PUSHED WELL INTO ERN OK THIS MORNING. THIS
FEATURE WILL SERVE AS FOCUS FOR WIDELY SCATTERED TO SCATTERED
CONVECTION TOMORROW AND INTO FRIDAY...ESPECIALLY OVER ERN OK. HEAT
ADVISORY CRITERIA WILL BE FLIRTED WITH ACROSS PARTS OF EAST
CENTRAL AND SOUTHEAST OKLAHOMA. WILL FOREGO AN ADVISORY AT THIS
TIME GIVEN MARGINAL VALUES EXPECTED ALONG WITH THE SHORT DURATION.
MODELS HAVE REMAINED FAIRLY CONSISTENT IN PUSHING THE BOUNDARY
FURTHER WEST BY LATER IN THE DAY FRIDAY...WITH MOST CONVECTION
ACROSS CENTRAL AN WESTERN SECTIONS OF OKLAHOMA. UPPER HIGH TO
REMAINED POSITIONED TO THE WEST OF THE FA THROUGH THE FORECAST
PERIOD...WITH SOME HEIGHT RISES NOTED THROUGH THE WEEKEND PER THE
GFS. LATER IN THE FORECAST CYCLE...ECMWF FLATTENS THE RIDGE AS AS
WAVE TRAVERSES THE CENTRAL PLAINS...WHILE THE GFS MAINTAINS
HIGHER HEIGHTS/WEAK NW FLOW. WILL KEEP FORECAST DRY FOR NOW BEYOND
FRIDAY. TEMPERATURES WILL INCREASE SOME OVER THE WEEKEND...BUT
WILL LIKELY NOT BE AS HOT AS OBSERVED THE LAST WEEK GIVEN THE
POSITIONING OF THE UPPER RIDGE TO THE WEST.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...06
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
506 AM EDT THU JUL 30 2015
.SYNOPSIS...
SHOWERS AND A FEW EMBEDDED THUNDERSTORMS WILL ACCOMPANY A COLD
FRONT FROM THE WESTERN ALLEGHENIES INTO THE CENTRAL RIDGE AND
VALLEY REGION EARLY TODAY...WITH ISOLATED STRONG TO SEVERE STORMS
POSSIBLE THIS AFTERNOON IN SOUTHEASTERN PENNSYLVANIA. A NOTICEABLY
DRIER AND LESS HUMID AIRMASS WILL OVERSPREAD THE AREA BEHIND THE
FRONT ON FRIDAY...WITH SEASONAL TEMPERATURES AND COMFORTABLE
HUMIDITY LEVELS TO CLOSE OUT THE MONTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR LOOP SHOWS A FRACTURED LINE/AXIS OF SHOWERS AND A FEW
EMBEDDED TSTMS MOVING INTO THE ALLEGHENIES EARLY THIS MORNING IN
ADVANCE OF SFC COLD FRONT. THE LATEST HRRR SHOWS THE FRONTAL PCPN
BAND REACHING A LINE FROM WELLSBORO TO STATE COLLEGE TO BEDFORD
BY 13Z.
A VERY MOIST AIRMASS WILL RESIDE AHEAD OF THE FRONT WITH 70+F
DEWPOINTS AND NARROW CORRIDOR OF PW VALUES AROUND 2.00 INCHES OR
+2SD ABOVE THE MEAN. THIS WILL HELP SUPPORT THE POTENTIAL FOR SOME
LOCALLY HEAVY DOWNPOURS...ESPECIALLY LATER THIS MORNING AND INTO
THE EARLY-MID AFTERNOON HOURS ACROSS PARTS OF THE ERN CWA WHERE
STRONGER INSTABILITY IS EXPECTED TO DEVELOP. THAT BEING SAID...SFC
HEATING MAY BE LIMITED AHEAD OF THE FRONT DUE TO CLOUDS/PCPN. THIS
WILL HAVE IMPLICATIONS FOR SEVERE WX POTENTIAL ACROSS ERN/SERN PA
WITH A CONDITIONAL/MARGINAL RISK TIED TO DEGREE OF DESTABILIZATION.
ALTHOUGH THE BEST LARGE-SCALE FORCING/HEIGHT FALLS AND BULK SHEAR
WILL BE DISPLACED TO THE NORTH FROM NY INTO THE NEW ENGLAND...A
FEW LOCALLY STRONG TO PERHAPS DAMAGING WIND GUSTS CANNOT BE RULED
OUT OVER THE ERN 1/3 OF THE CWA WHERE SPC HAS MAINTAINED A MRGL
RISK. SCT STORMS SHOULD PUSH EAST AND EXIT THE SE ZONES AROUND
5PM/21Z WITH A PLEASANT EVENING IN STORE FOR THE AREA.
MAX TEMPS WILL TOP OUT AROUND 90F ACROSS THE MID TO LOWER SUSQ
VALLEY...WITH HEAT INDEX VALUES APPROACHING 100F FOR A SHORT
DURATION. RELIEF FROM THE HEAT/HUMIDITY WILL ARRIVE BY TONIGHT AS
A NOTICEABLY DRIER LOW PW AIRMASS OVERSPREADS THE AREA FROM WEST
TO EAST BEHIND THE COLD FRONTAL PASSAGE.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
FAIR WEATHER WITH PLENTY OF SUNSHINE...SEASONAL TEMPERATURES AND
COMFORTABLE HUMIDITY IS EXPECTED ON FRIDAY. STRONGER NW FLOW ALOFT
WILL EXTEND FROM THE NORTHERN PLAINS THROUGH THE GREAT LAKES INTO
THE WEEKEND...IN BETWEEN AN EXPANSIVE UPPER LEVEL RIDGE OVER THE
SOUTHERN ROCKIES/PLAINS AND UPPER TROUGH/CLOSED LOW INVOF HUDSON
BAY. THE FIRST...IN WHAT WILL BE A SERIES OF MOISTURE STARVED NRN
STREAM COLD FRONTS...WILL MOVE INTO THE AREA ON SATURDAY AND BRING
THE RISK OF SCT SHOWERS/ISOLATED TSTMS. MODEL CONSENSUS FAVORS NW
AND N-CENTRAL PA WITH THE HIGHEST POPS /30-40 PCT/ FOR DAY 3/SAT.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
LITTLE CHANGE IS ANTICIPATED IN WHAT SHOULD BE A STABLE LARGE
SCALE FLOW PATTERN ACROSS THE CONUS DURING THE FIRST WEEK OF
AUGUST. UPPER RIDGE WILL CONTINUE TO DOMINATE OUT WEST WHILE A
BROAD UPPER TROUGH EXTENDS SWD FROM EASTERN CANADA ACROSS THE ERN
U.S. TEMPERATURES SHOULD AVG NEAR NORMAL INTO EARLY NEXT WEEK
BEFORE TRENDING COOLER LATER IN THE WEEK. CONFIDENCE IS LOW ON
TIMING OF PCPN CHANCES ASSOCD WITH NRN STREAM FRONTAL SYSTEMS.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
WIDESPREAD VFR WILL GIVE WAY TO INCREASING CLOUDS AND THE
DEVELOPMENT OF SOME HAZE/THIN FOG. MOST TERMINALS WILL SEE VIZ
SLIP TO 2-4 MILES IN THE HOURS AFTER MIDNIGHT WITH SOME LOW CLOUDS
LIKELY ADVECTING NORTH INTO SOUTH-CENTRAL AREAS IN THE VERY HUMID
TROPICAL AIRMASS.
BY MORNING...SHOWERS AND SCATTERED THUNDERSTORMS WILL BEGIN
MOVING INTO WESTERN AREAS AHEAD OF A COLD FRONT. THE FRONT WILL BE
MOVING THROUGH EASTERN PA BY EARLY TO MID AFTERNOON SO
SHOWERS/STORMS WILL NOT BE AN ALL DAY EVENT AT AREA AIRPORTS.
DRIER CONDITIONS WILL DEVELOP WEST TO EAST IN THE WAKE OF THE
FRONT.
OUTLOOK...
FRI...MAINLY VFR.
SAT...MAINLY VFR...SCATTERED SHOWERS/THUNDERSTORMS.
SUN...MAINLY VFR.
MON...MAINLY VFR...SCATTERED SHOWERS/THUNDERSTORMS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...STEINBUGL
NEAR TERM...STEINBUGL
SHORT TERM...STEINBUGL
LONG TERM...STEINBUGL
AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
136 PM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE INTO THE REGION FROM THE NORTHWEST
TODAY AND SETTLE SOUTHEAST OF THE AREA TONIGHT THROUGH FRIDAY. THE
FRONT AND ASSOCIATED DEEPER MOISTURE WILL LIKELY REMAIN CONFINED
ALONG THE SOUTHEAST COASTLINE THROUGH THE WEEKEND...WITH SLIGHTLY
COOLER TEMPERATURES AND MUCH DRIER AIR EXPECTED OVER THE FORECAST
AREA. LOW LEVEL MOISTURE WILL GRADUALLY RETURN EARLY NEXT WEEK AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 130 PM...ISOLATED TO WIDELY SCATTERED CONVECTION HAS BEGUN TO
DEVELOP ACRS THE CWFA...IN LINE WITH THE CURRENT POP TRENDS. TEMPS
AND DEWPTS ARE ALSO ON TRACK. SO NO SIGNIFICANT CHANGES WITH THIS
UPDATE.
AS OF 1015 AM...THE 12Z SFC ANALYSIS SHOWED THE COLD FRONT PUSHING
INTO THE SMOKIES AND GREAT TENN VALLEY. THE FRONT WILL CONTINUE TO
PUSH ACRS THE MTNS THRU MIDDAY...THEN ACRS THE PIEDMONT THIS AFTN.
THERE IS LESS CLOUD COVER AT THIS TIME OF DAY THAN THE LAST FEW
DAYS. SO TEMPS ARE WARMING QUICKLY...DESPITE HUMID BL...WITH DEWPTS
STILL IN THE LWR-MID 70S. THIS IS RESULTING IN SBCAPE ALREADY IN THE
1500-2500 J/KG RANGE ON THE SPC MESOANALYSIS PAGE ACRS THE PIEDMONT.
I HAVE BUMPED MAX TEMPS UP A DEG OR TWO GIVEN THE TRENDS. AS FOR
POPS...ONE WOULD EXPECT DECENT COVERAGE OF SHWRS AND TSTMS...GIVEN
DECENT INSTBY AND A BOUNDARY WORKING THRU THE AREA. HOWEVER...THE
LATEST CAMS ARE A BIT MUTED. I TRIED BLENDING IN CAM POP...BUT THAT
DROPPED POP DOWN ACRS MUCH OF THE AREA. SO I PRETTY MUCH KEPT POPS
AS IS...WHICH IS IN THE 30-40 PCT RANGE. SEVERE THREAT IS STILL
MARGINAL...WITH WIND BEING THE MAIN THREAT.
AS OF 650 AM...THE FORECAST APPEARS IN GOOD SHAPE. I WILL TAYLOR
POPS TO REFLECT LIGHT RETURNS OVER THE WESTERN NC MTNS. IN
ADDITION...I WILL REDUCE FOG MENTION.
AS OF 345 AM...LATEST SFC ANALYSIS INDICATED THAT A COLD FRONT WAS
CROSSING MIDDLE KY AND TN...MOVING EAST. BASED ON RECENT OBSERVATION
TRENDS AND MODEL GUIDANCE...THE COLD FRONT IS EXPECTED TO SWEEP
ACROSS THE SOUTHERN APPALACHIANS AROUND MID DAY...REACHING THE
PIEDMONT LATE THIS AFTERNOON/EARLY EVENING. MOS GUIDANCE INDICATES
THAT HIGH TEMPERATURES SHOULD RANGE IN THE MID 80S WITHIN THE MTN
VALLEYS TO LOW TO MID 90S EAST. SFC DEWPOINTS ARE FORECAST TO REMAIN
BETWEEN 66 TO 71 DEGREES DURING THE HEAT OF THE AFTERNOON. MODEL
SOUNDINGS AND PLAIN VIEW SHOW CAPES GENERALLY RANGING NEAR 2000
J/KG. NAM AND RAP DCAPE INCREASE TO VALUES GREATER THAN 1000 J/KG
ALONG AND AHEAD OF THE FRONT. BASED ON THE NAM...A BROKEN BAND OF
TSRA SHOULD DEVELOP ALONG AND AHEAD OF THE FRONT. THE CONVECTION MAY
CROSS THE MTNS DURING THE MORNING DAYLIGHT HOURS...SLIDING ACROSS
THE PIEDMONT DURING THE EARLY TO MID AFTERNOON. IN THE WAKE OF THE
BAND...SCT DISCRETE CELLS MAY DEVELOP...MOVING EAST BY SUNSET. GIVEN
THE MODERATE CAPE...A WIDE FIELD OF DCAPE...AND THE DAYTIME PASSAGE
OF A COLD FRONT...IT APPEARS THAT SEVERAL STORMS COULD PRODUCE
DAMAGING WIND GUSTS. HAIL IS POSSIBLE...BUT HIGH WBZ SHOULD LIMIT
HAIL SIZE TO LESS THAN SEVERE. WE WILL HIGHLIGHT THE SEVERE
POTENTIAL IN THE HWO.
TONIGHT...WEAK CAA AND FALLING DEWPOINTS WILL INCREASE FROM NW TO SE
IN THE WAKE OF THE FRONT. SKY COVER SHOULD CLEAR FROM WEST TO
EAST...WITH MOST OF THE AREA UNDER LITTLE CLOUD COVER BY DAWN
FRIDAY. GIVEN THE LIGHT NNW WINDS...THE COOLEST THICKNESSES SHOULD
REMAIN OVER THE MTNS. I WILL FORECAST LOWS IN THE 50S AND 60S ACROSS
THE MTNS...WITH LOW 70S EAST.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM EDT THURSDAY...A BROAD EASTERN TROUGH WILL DEVELOP ON
FRIDAY. UNDER THIS TROUGH...DRIER AIR WILL SPILL INTO THE REGION
FROM THE NORTH AS A DEPARTING SFC FRONT SETTLES TO THE SOUTHEAST
COAST AND SURFACE HIGH PRESSURE STRETCHES FROM THE MID MS RIVER
VALLEY TO THE SRN AND CENTRAL APPALACHIANS. DEWPOINTS
ADVECTING/MIXING WELL DOWN IN THE 50S IN MOST AREAS WILL LARGELY
PRECLUDE ANY CONVECTION ON FRIDAY...WITH ANY ISOLD SHOWERS CONFINED
TO THE EXTREME LOWER PIEDMONT DURING THE AFTERNOON HOURS.
THE EASTERN TROUGH WILL AMPLIFY OVER THE WEEKEND AS A SERIES OF
SHORTWAVES MOVE THROUGH THE MEAN TROUGH AXIS. DRY SFC HIGH PRESSURE
WILL REMAIN IN PLACE ON SATURDAY...WITH A WEAKLY REINFORCING SURFACE
FRONT APPROACHING FROM THE NORTH LATE IN THE DAY. ISOLATED SHOWER OR
WEAK TSTM COVERAGE MAY OCCUR LATE DAY JUST N OF THE REGION ALONG THE
FRONT AND ALSO ACROSS THE SOUTHERN TIER WHERE DEWPOINTS MAY RECOVER
EVER SO SLIGHTLY.
THE AIRMASS WILL CONTINUE TO MODIFY ON SUNDAY...BUT WITH MOISTURE
VERY SLOW TO RETURN. THE SHORTWAVES MOVING THROUGH THE ERN TROUGH
WILL REMAIN DIFFICULT TO TIME...BUT THERE IS DEVELOPING CONSENSUS ON
STRONGER Q VECTOR CONVERGENCE WITH A SHORTWAVE LATE SUNDAY INTO
SUNDAY NIGHT JUST AS MOISTURE REBOUNDS SLIGHTLY. THIS WILL WARRANT
BETTER ISOLD COVERAGE OF SHRA/TSRA LATE SUNDAY...WITH MORE OF A NON
DIURNAL ISOLD NIGHTTIME POP MENTION ON SUNDAY NIGHT. TEMPERATURES
WILL REMAIN NEAR TO SLIGHTLY ABOVE CLIMO THROUGH THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 330 AM EDT THURSDAY...MODEL CONSENSUS DEPICTS SLIGHT
SHALLOWING OF THE ERN TROUGH MONDAY THROUGH WEDNESDAY. MEANWHILE...
A MORE VIGOROUS SURFACE COLD FRONT WILL MOVE SOUTH OF THE GREAT
LAKES ON MONDAY AND APPROACH THE FORECAST AREA FROM THE NORTH ON
TUESDAY. THERE IS CONSIDERABLE MEDIUM RANGE MODEL SPREAD ON HOW FAR
SOUTH THE FRONT GETS...WITH THE ECMWF GENERALLY STALLING THE
BOUNDARY N OF THE AREA...WHILE THE GFS AND ASSOCIATED ENSEMBLES
BRING IT AT LEAST INTO THE NRN TIER BEFORE TURNING IT AROUND AS A
WARM FRONT ON WEDNESDAY. A CONSENSUS APPROACH WILL KEEP THE BOUNDARY
N OF THE AREA BUT FEATURE AN UPTICK IN DIURNAL AFTN CONVECTIVE
COVERAGE AHEAD OF THE FRONT AS THE BOUNDARY LAYER CONTINUES TO
REBOUND AND LAPSE RATES FURTHER STEEPEN ALOFT. TEMPERATURES WILL
GRADUALLY WARM THROUGH THE PERIOD.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AT KCLT...A RATHER WEAK AND NEBULOUS COLD FRONT WILL CROSS THE KCLT
AREA THIS EVENING. IT IS HELPING TO INITIATE CONVECTION ACRS THE
BLUE AND NC FOOTHILLS N OF KCLT...AND THAT ACTIVITY WILL DRIFT SOUTH
ACRS THE AREA BETWEEN 19-22Z. GUIDANCE HAS SOME ISOLATED CONVECTION
DEVELOPING ALONG THE TRAILING FRONT AFTER 00Z THIS EVENING ACRS THE
NC PIEDMONT. CONFIDENCE IS LOW ON THIS...AS DRY AIR WILL BEGIN TO
FILTER IN AND THE BL WILL BE STABILIZING. SO WILL NOT MENTION ANY
PRECIP BEYOND THE TEMPO. OVERNIGHT...THERE IS BETTER AGREEMENT ON
LINGERING VFR STRATOCU WELL INTO THE NIGHT...AS MOISTURE LINGERS
BELOW A DEVELOPING INVERSION AROUND 5000-7000 FT AGL. DRY AIR WILL
EVENTUALLY CLEAR THIS OUT FRIDAY MORNING. WINDS ARE ALREADY FAVORING
A N DIRECTION AHEAD OF THE FRONT...AND WILL CONTINUE TO THRU THE
PERIOD...INCREASING BEHIND THE FRONT TO AROUND 8-10 KTS BEFORE
DAYBREAK FRIDAY.
ELSEWHERE...SCATTERED CONVECTION THIS AFTN SEEMS TO WARRANT VCTS FOR
ALL SITES. CLOUD BASES WILL HOVER AROUND 4500-6000 FT...THEN LIFT TO
AROUND 7000-8000 FT BEHIND A PASSING COLD FRONT THIS EVENING. THE
NAM HAS POTENTIAL MVFR CIGS AT KAVL FOR A BRIEF TIME THIS
EVENING...SO WILL MENTION SCT FOR NOW. A N WIND WILL INCREASE
SLIGHTLY OVERNIGHT...WITH DRY AIR WORKING IN. SO NOT EXPECTING ANY
FOG OR LOW CLOUDS OUTSIDE THE LITTLE TN RIVER VALLEY. THE VFR-LVL
STRATOCU IS EXPECTED TO DISSIPATE FRIDAY MORNING.
OUTLOOK...DRY HIGH PRESSURE WITH BUILD IN ACRS THE REGION
FRIDAY...ALLOWING FOR GENERALLY DRY AND QUIET WEATHER THROUGH THE
WEEKEND. A GRADUAL INCREASE IN CHANCES FOR SHOWERS/THUNDERSTORMS AND
RESTRICTIONS WILL RETURN FOR THE START OF THE NEW WORK WEEK.
CONFIDENCE TABLE...
17-23Z 23-05Z 05-11Z 11-12Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% LOW 56% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...ARK/NED
SHORT TERM...HG
LONG TERM...HG
AVIATION...ARK
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1027 AM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE INTO THE REGION FROM THE NORTHWEST
TODAY AND SETTLE SOUTHEAST OF THE AREA TONIGHT THROUGH FRIDAY. THE
FRONT AND ASSOCIATED DEEPER MOISTURE WILL LIKELY REMAIN CONFINED
ALONG THE SOUTHEAST COASTLINE THROUGH THE WEEKEND...WITH SLIGHTLY
COOLER TEMPERATURES AND MUCH DRIER AIR EXPECTED OVER THE FORECAST
AREA. LOW LEVEL MOISTURE WILL GRADUALLY RETURN EARLY NEXT WEEK AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM...THE 12Z SFC ANALYSIS SHOWED THE COLD FRONT PUSHING
INTO THE SMOKIES AND GREAT TENN VALLEY. THE FRONT WILL CONTINUE TO
PUSH ACRS THE MTNS THRU MIDDAY...THEN ACRS THE PIEDMONT THIS AFTN.
THERE IS LESS CLOUD COVER AT THIS TIME OF DAY THAN THE LAST FEW
DAYS. SO TEMPS ARE WARMING QUICKLY...DESPITE HUMID BL...WITH DEWPTS
STILL IN THE LWR-MID 70S. THIS IS RESULTING IN SBCAPE ALREADY IN THE
1500-2500 J/KG RANGE ON THE SPC MESOANALYSIS PAGE ACRS THE PIEDMONT.
I HAVE BUMPED MAX TEMPS UP A DEG OR TWO GIVEN THE TRENDS. AS FOR
POPS...ONE WOULD EXPECT DECENT COVERAGE OF SHWRS AND TSTMS...GIVEN
DECENT INSTBY AND A BOUNDARY WORKING THRU THE AREA. HOWEVER...THE
LATEST CAMS ARE A BIT MUTED. I TRIED BLENDING IN CAM POP...BUT THAT
DROPPED POP DOWN ACRS MUCH OF THE AREA. SO I PRETTY MUCH KEPT POPS
AS IS...WHICH IS IN THE 30-40 PCT RANGE. SEVERE THREAT IS STILL
MARGINAL...WITH WIND BEING THE MAIN THREAT.
AS OF 650 AM...THE FORECAST APPEARS IN GOOD SHAPE. I WILL TAYLOR
POPS TO REFLECT LIGHT RETURNS OVER THE WESTERN NC MTNS. IN
ADDITION...I WILL REDUCE FOG MENTION.
AS OF 345 AM...LATEST SFC ANALYSIS INDICATED THAT A COLD FRONT WAS
CROSSING MIDDLE KY AND TN...MOVING EAST. BASED ON RECENT OBSERVATION
TRENDS AND MODEL GUIDANCE...THE COLD FRONT IS EXPECTED TO SWEEP
ACROSS THE SOUTHERN APPALACHIANS AROUND MID DAY...REACHING THE
PIEDMONT LATE THIS AFTERNOON/EARLY EVENING. MOS GUIDANCE INDICATES
THAT HIGH TEMPERATURES SHOULD RANGE IN THE MID 80S WITHIN THE MTN
VALLEYS TO LOW TO MID 90S EAST. SFC DEWPOINTS ARE FORECAST TO REMAIN
BETWEEN 66 TO 71 DEGREES DURING THE HEAT OF THE AFTERNOON. MODEL
SOUNDINGS AND PLAIN VIEW SHOW CAPES GENERALLY RANGING NEAR 2000
J/KG. NAM AND RAP DCAPE INCREASE TO VALUES GREATER THAN 1000 J/KG
ALONG AND AHEAD OF THE FRONT. BASED ON THE NAM...A BROKEN BAND OF
TSRA SHOULD DEVELOP ALONG AND AHEAD OF THE FRONT. THE CONVECTION MAY
CROSS THE MTNS DURING THE MORNING DAYLIGHT HOURS...SLIDING ACROSS
THE PIEDMONT DURING THE EARLY TO MID AFTERNOON. IN THE WAKE OF THE
BAND...SCT DISCRETE CELLS MAY DEVELOP...MOVING EAST BY SUNSET. GIVEN
THE MODERATE CAPE...A WIDE FIELD OF DCAPE...AND THE DAYTIME PASSAGE
OF A COLD FRONT...IT APPEARS THAT SEVERAL STORMS COULD PRODUCE
DAMAGING WIND GUSTS. HAIL IS POSSIBLE...BUT HIGH WBZ SHOULD LIMIT
HAIL SIZE TO LESS THAN SEVERE. WE WILL HIGHLIGHT THE SEVERE
POTENTIAL IN THE HWO.
TONIGHT...WEAK CAA AND FALLING DEWPOINTS WILL INCREASE FROM NW TO SE
IN THE WAKE OF THE FRONT. SKY COVER SHOULD CLEAR FROM WEST TO
EAST...WITH MOST OF THE AREA UNDER LITTLE CLOUD COVER BY DAWN
FRIDAY. GIVEN THE LIGHT NNW WINDS...THE COOLEST THICKNESSES SHOULD
REMAIN OVER THE MTNS. I WILL FORECAST LOWS IN THE 50S AND 60S ACROSS
THE MTNS...WITH LOW 70S EAST.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM EDT THURSDAY...A BROAD EASTERN TROUGH WILL DEVELOP ON
FRIDAY. UNDER THIS TROUGH...DRIER AIR WILL SPILL INTO THE REGION
FROM THE NORTH AS A DEPARTING SFC FRONT SETTLES TO THE SOUTHEAST
COAST AND SURFACE HIGH PRESSURE STRETCHES FROM THE MID MS RIVER
VALLEY TO THE SRN AND CENTRAL APPALACHIANS. DEWPOINTS
ADVECTING/MIXING WELL DOWN IN THE 50S IN MOST AREAS WILL LARGELY
PRECLUDE ANY CONVECTION ON FRIDAY...WITH ANY ISOLD SHOWERS CONFINED
TO THE EXTREME LOWER PIEDMONT DURING THE AFTERNOON HOURS.
THE EASTERN TROUGH WILL AMPLIFY OVER THE WEEKEND AS A SERIES OF
SHORTWAVES MOVE THROUGH THE MEAN TROUGH AXIS. DRY SFC HIGH PRESSURE
WILL REMAIN IN PLACE ON SATURDAY...WITH A WEAKLY REINFORCING SURFACE
FRONT APPROACHING FROM THE NORTH LATE IN THE DAY. ISOLATED SHOWER OR
WEAK TSTM COVERAGE MAY OCCUR LATE DAY JUST N OF THE REGION ALONG THE
FRONT AND ALSO ACROSS THE SOUTHERN TIER WHERE DEWPOINTS MAY RECOVER
EVER SO SLIGHTLY.
THE AIRMASS WILL CONTINUE TO MODIFY ON SUNDAY...BUT WITH MOISTURE
VERY SLOW TO RETURN. THE SHORTWAVES MOVING THROUGH THE ERN TROUGH
WILL REMAIN DIFFICULT TO TIME...BUT THERE IS DEVELOPING CONSENSUS ON
STRONGER Q VECTOR CONVERGENCE WITH A SHORTWAVE LATE SUNDAY INTO
SUNDAY NIGHT JUST AS MOISTURE REBOUNDS SLIGHTLY. THIS WILL WARRANT
BETTER ISOLD COVERAGE OF SHRA/TSRA LATE SUNDAY...WITH MORE OF A NON
DIURNAL ISOLD NIGHTTIME POP MENTION ON SUNDAY NIGHT. TEMPERATURES
WILL REMAIN NEAR TO SLIGHTLY ABOVE CLIMO THROUGH THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 330 AM EDT THURSDAY...MODEL CONSENSUS DEPICTS SLIGHT
SHALLOWING OF THE ERN TROUGH MONDAY THROUGH WEDNESDAY. MEANWHILE...
A MORE VIGOROUS SURFACE COLD FRONT WILL MOVE SOUTH OF THE GREAT
LAKES ON MONDAY AND APPROACH THE FORECAST AREA FROM THE NORTH ON
TUESDAY. THERE IS CONSIDERABLE MEDIUM RANGE MODEL SPREAD ON HOW FAR
SOUTH THE FRONT GETS...WITH THE ECMWF GENERALLY STALLING THE
BOUNDARY N OF THE AREA...WHILE THE GFS AND ASSOCIATED ENSEMBLES
BRING IT AT LEAST INTO THE NRN TIER BEFORE TURNING IT AROUND AS A
WARM FRONT ON WEDNESDAY. A CONSENSUS APPROACH WILL KEEP THE BOUNDARY
N OF THE AREA BUT FEATURE AN UPTICK IN DIURNAL AFTN CONVECTIVE
COVERAGE AHEAD OF THE FRONT AS THE BOUNDARY LAYER CONTINUES TO
REBOUND AND LAPSE RATES FURTHER STEEPEN ALOFT. TEMPERATURES WILL
GRADUALLY WARM THROUGH THE PERIOD.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
AT KCLT...THE PRIMARY FORECAST CHALLENGE WILL BE THE TIMING OF A
SWEEPING COLD FRONT AND ASSOCIATED WIND SHIFT. AT 10Z...THE COLD
FRONT WAS ANALYZED OVER MIDDLE KY/TN. THE COLD FRONT IS FORECAST TO
SWEEP EAST TODAY...REACHING THE NC PIEDMONT LATE THIS AFTERNOON. I
WILL FORECAST LIGHT SW WINDS ACROSS THE CLT TERMINAL THROUGH THE
MORNING HOURS...VEERING WNW BY 17Z. A BROKEN BAND OF SHRA/TSRA WILL
LIKELY FORM AHEAD OF THE FRONT...TRACKING SE. BASED ON THE 6Z
NAM...THE MOST LIKELY TIME WINDOW FOR CONVECTION SHOULD OCCUR
BETWEEN 19Z TO 22Z...HIGHLIGHTED WITH A TEMPO. IN THE WAKE OF THE
FRONT...NNW WINDS SHOULD STRENGTHEN TO 5 TO 10KTS WITH VFR
OVERNIGHT CONDITIONS.
ELSEWHERE...SUNRISE TEMPERATURES HAVE CLOSED IN ON CROSSOVER VALUES
YIELDING LIGHT FOG AT KGSP AND KGMU. KAVL HAS SEEN SOME VLIFR CLOUDS
THIS MORNING...BUT LATEST OBS INDICATE THAT THESE CEILINGS HAVE
DISSIPATED. I WILL LIMIT SKY TO SCT003 IN THE INITIAL LINE OF THE
KAVL TAF...WILL MONITOR CLOSELY THIS MORNING. PRE FRONTAL CONVECTION
SHOULD FORM AHEAD OF THE COLD FRONT...WITH COVERAGE INCREASING AS IT
MOVES EAST. I WILL USE A TEMPO FOR EACH SITE EAST OF THE MTNS
INDICATING A EARLY TO MID AFTERNOON BAND OF TSRA. AFTER THE
CONVECTION...WINDS SHOULD VEER NNW AND REMAIN THROUGH THE REST OF
THE TAF PERIOD.
OUTLOOK...HIGH PRESSURE WITH BUILD IN BEHIND A PASSING COLD FRONT
LATE ON THURSDAY ALLOWING FOR GENERALLY DRY AND QUIET WEATHER
THROUGH THE WEEKEND. CHANCES FOR SHOWERS/THUNDERSTORMS AND THUS
RESTRICTIONS WILL RETURN FOR THE START OF THE NEW WORK WEEK.
CONFIDENCE TABLE...
14-20Z 20-02Z 02-08Z 08-12Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 98% HIGH 88% MED 67% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 88% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...ARK/NED
SHORT TERM...HG
LONG TERM...HG
AVIATION...NED
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
655 AM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE INTO THE REGION FROM THE NORTHWEST
TODAY AND SETTLE SOUTHEAST OF THE AREA TONIGHT THROUGH FRIDAY. THE
FRONT AND ASSOCIATED DEEPER MOISTURE WILL LIKELY REMAIN CONFINED
ALONG THE SOUTHEAST COASTLINE THROUGH THE WEEKEND...WITH SLIGHTLY
COOLER TEMPERATURES AND MUCH DRIER AIR EXPECTED OVER THE FORECAST
AREA. LOW LEVEL MOISTURE WILL GRADUALLY RETURN EARLY NEXT WEEK AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 650 AM...THE FORECAST APPEARS IN GOOD SHAPE. I WILL TAYLOR
POPS TO REFLECT LIGHT RETURNS OVER THE WESTERN NC MTNS. IN
ADDITION...I WILL REDUCE FOG MENTION.
AS OF 345 AM...LATEST SFC ANALYSIS INDICATED THAT A COLD FRONT WAS
CROSSING MIDDLE KY AND TN...MOVING EAST. BASED ON RECENT OBSERVATION
TRENDS AND MODEL GUIDANCE...THE COLD FRONT IS EXPECTED TO SWEEP
ACROSS THE SOUTHERN APPALACHIANS AROUND MID DAY...REACHING THE
PIEDMONT LATE THIS AFTERNOON/EARLY EVENING. MOS GUIDANCE INDICATES
THAT HIGH TEMPERATURES SHOULD RANGE IN THE MID 80S WITHIN THE MTN
VALLEYS TO LOW TO MID 90S EAST. SFC DEWPOINTS ARE FORECAST TO REMAIN
BETWEEN 66 TO 71 DEGREES DURING THE HEAT OF THE AFTERNOON. MODEL
SOUNDINGS AND PLAIN VIEW SHOW CAPES GENERALLY RANGING NEAR 2000
J/KG. NAM AND RAP DCAPE INCREASE TO VALUES GREATER THAN 1000 J/KG
ALONG AND AHEAD OF THE FRONT. BASED ON THE NAM...A BROKEN BAND OF
TSRA SHOULD DEVELOP ALONG AND AHEAD OF THE FRONT. THE CONVECTION MAY
CROSS THE MTNS DURING THE MORNING DAYLIGHT HOURS...SLIDING ACROSS
THE PIEDMONT DURING THE EARLY TO MID AFTERNOON. IN THE WAKE OF THE
BAND...SCT DISCRETE CELLS MAY DEVELOP...MOVING EAST BY SUNSET. GIVEN
THE MODERATE CAPE...A WIDE FIELD OF DCAPE...AND THE DAYTIME PASSAGE
OF A COLD FRONT...IT APPEARS THAT SEVERAL STORMS COULD PRODUCE
DAMAGING WIND GUSTS. HAIL IS POSSIBLE...BUT HIGH WBZ SHOULD LIMIT
HAIL SIZE TO LESS THAN SEVERE. WE WILL HIGHLIGHT THE SEVERE
POTENTIAL IN THE HWO.
TONIGHT...WEAK CAA AND FALLING DEWPOINTS WILL INCREASE FROM NW TO SE
IN THE WAKE OF THE FRONT. SKY COVER SHOULD CLEAR FROM WEST TO
EAST...WITH MOST OF THE AREA UNDER LITTLE CLOUD COVER BY DAWN
FRIDAY. GIVEN THE LIGHT NNW WINDS...THE COOLEST THICKNESSES SHOULD
REMAIN OVER THE MTNS. I WILL FORECAST LOWS IN THE 50S AND 60S ACROSS
THE MTNS...WITH LOW 70S EAST.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM EDT THURSDAY...A BROAD EASTERN TROUGH WILL DEVELOP ON
FRIDAY. UNDER THIS TROUGH...DRIER AIR WILL SPILL INTO THE REGION
FROM THE NORTH AS A DEPARTING SFC FRONT SETTLES TO THE SOUTHEAST
COAST AND SURFACE HIGH PRESSURE STRETCHES FROM THE MID MS RIVER
VALLEY TO THE SRN AND CENTRAL APPALACHIANS. DEWPOINTS
ADVECTING/MIXING WELL DOWN IN THE 50S IN MOST AREAS WILL LARGELY
PRECLUDE ANY CONVECTION ON FRIDAY...WITH ANY ISOLD SHOWERS CONFINED
TO THE EXTREME LOWER PIEDMONT DURING THE AFTERNOON HOURS.
THE EASTERN TROUGH WILL AMPLIFY OVER THE WEEKEND AS A SERIES OF
SHORTWAVES MOVE THROUGH THE MEAN TROUGH AXIS. DRY SFC HIGH PRESSURE
WILL REMAIN IN PLACE ON SATURDAY...WITH A WEAKLY REINFORCING SURFACE
FRONT APPROACHING FROM THE NORTH LATE IN THE DAY. ISOLATED SHOWER OR
WEAK TSTM COVERAGE MAY OCCUR LATE DAY JUST N OF THE REGION ALONG THE
FRONT AND ALSO ACROSS THE SOUTHERN TIER WHERE DEWPOINTS MAY RECOVER
EVER SO SLIGHTLY.
THE AIRMASS WILL CONTINUE TO MODIFY ON SUNDAY...BUT WITH MOISTURE
VERY SLOW TO RETURN. THE SHORTWAVES MOVING THROUGH THE ERN TROUGH
WILL REMAIN DIFFICULT TO TIME...BUT THERE IS DEVELOPING CONSENSUS ON
STRONGER Q VECTOR CONVERGENCE WITH A SHORTWAVE LATE SUNDAY INTO
SUNDAY NIGHT JUST AS MOISTURE REBOUNDS SLIGHTLY. THIS WILL WARRANT
BETTER ISOLD COVERAGE OF SHRA/TSRA LATE SUNDAY...WITH MORE OF A NON
DIURNAL ISOLD NIGHTTIME POP MENTION ON SUNDAY NIGHT. TEMPERATURES
WILL REMAIN NEAR TO SLIGHTLY ABOVE CLIMO THROUGH THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 330 AM EDT THURSDAY...MODEL CONSENSUS DEPICTS SLIGHT
SHALLOWING OF THE ERN TROUGH MONDAY THROUGH WEDNESDAY. MEANWHILE...
A MORE VIGOROUS SURFACE COLD FRONT WILL MOVE SOUTH OF THE GREAT
LAKES ON MONDAY AND APPROACH THE FORECAST AREA FROM THE NORTH ON
TUESDAY. THERE IS CONSIDERABLE MEDIUM RANGE MODEL SPREAD ON HOW FAR
SOUTH THE FRONT GETS...WITH THE ECMWF GENERALLY STALLING THE
BOUNDARY N OF THE AREA...WHILE THE GFS AND ASSOCIATED ENSEMBLES
BRING IT AT LEAST INTO THE NRN TIER BEFORE TURNING IT AROUND AS A
WARM FRONT ON WEDNESDAY. A CONSENSUS APPROACH WILL KEEP THE BOUNDARY
N OF THE AREA BUT FEATURE AN UPTICK IN DIURNAL AFTN CONVECTIVE
COVERAGE AHEAD OF THE FRONT AS THE BOUNDARY LAYER CONTINUES TO
REBOUND AND LAPSE RATES FURTHER STEEPEN ALOFT. TEMPERATURES WILL
GRADUALLY WARM THROUGH THE PERIOD.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AT KCLT...THE PRIMARY FORECAST CHALLENGE WILL BE THE TIMING OF A
SWEEPING COLD FRONT AND ASSOCIATED WIND SHIFT. AT 10Z...THE COLD
FRONT WAS ANALYZED OVER MIDDLE KY/TN. THE COLD FRONT IS FORECAST TO
SWEEP EAST TODAY...REACHING THE NC PIEDMONT LATE THIS AFTERNOON. I
WILL FORECAST LIGHT SW WINDS ACROSS THE CLT TERMINAL THROUGH THE
MORNING HOURS...VEERING WNW BY 17Z. A BROKEN BAND OF SHRA/TSRA WILL
LIKELY FORM AHEAD OF THE FRONT...TRACKING SE. BASED ON THE 6Z
NAM...THE MOST LIKELY TIME WINDOW FOR CONVECTION SHOULD OCCUR
BETWEEN 19Z TO 22Z...HIGHLIGHTED WITH A TEMPO. IN THE WAKE OF THE
FRONT...NNW WINDS SHOULD STRENGTHEN TO 5 TO 10KTS WITH VFR
OVERNIGHT CONDITIONS.
ELSEWHERE...SUNRISE TEMPERATURES HAVE CLOSED IN ON CROSSOVER VALUES
YIELDING LIGHT FOG AT KGSP AND KGMU. KAVL HAS SEEN SOME VLIFR CLOUDS
THIS MORNING...BUT LATEST OBS INDICATE THAT THESE CEILINGS HAVE
DISSIPATED. I WILL LIMIT SKY TO SCT003 IN THE INITIAL LINE OF THE
KAVL TAF...WILL MONITOR CLOSELY THIS MORNING. PRE FRONTAL CONVECTION
SHOULD FORM AHEAD OF THE COLD FRONT...WITH COVERAGE INCREASING AS IT
MOVES EAST. I WILL USE A TEMPO FOR EACH SITE EAST OF THE MTNS
INDICATING A EARLY TO MID AFTERNOON BAND OF TSRA. AFTER THE
CONVECTION...WINDS SHOULD VEER NNW AND REMAIN THROUGH THE REST OF
THE TAF PERIOD.
OUTLOOK...HIGH PRESSURE WITH BUILD IN BEHIND A PASSING COLD FRONT
LATE ON THURSDAY ALLOWING FOR GENERALLY DRY AND QUIET WEATHER
THROUGH THE WEEKEND. CHANCES FOR SHOWERS/THUNDERSTORMS AND THUS
RESTRICTIONS WILL RETURN FOR THE START OF THE NEW WORK WEEK.
CONFIDENCE TABLE...
11-17Z 17-23Z 23-05Z 05-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL LOW 31% HIGH 100% HIGH 100% LOW 58%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...NED
SHORT TERM...HG
LONG TERM...HG
AVIATION...NED
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
351 AM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL MOVE INTO THE REGION FROM THE NORTHWEST
TODAY AND SETTLE SOUTHEAST OF THE AREA TONIGHT THROUGH FRIDAY. THE
FRONT AND ASSOCIATED DEEPER MOISTURE WILL LIKELY REMAIN CONFINED
ALONG THE SOUTHEAST COASTLINE THROUGH THE WEEKEND...WITH SLIGHTLY
COOLER TEMPERATURES AND MUCH DRIER AIR EXPECTED OVER THE FORECAST
AREA. LOW LEVEL MOISTURE WILL GRADUALLY RETURN EARLY NEXT WEEK AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 345 AM...LATEST SFC ANALYSIS INDICATED THAT A COLD FRONT WAS
CROSSING MIDDLE KY AND TN...MOVING EAST. BASED ON RECENT OBSERVATION
TRENDS AND MODEL GUIDANCE...THE COLD FRONT IS EXPECTED TO SWEEP
ACROSS THE SOUTHERN APPALACHIANS AROUND MID DAY...REACHING THE
PIEDMONT LATE THIS AFTERNOON/EARLY EVENING. MOS GUIDANCE INDICATES
THAT HIGH TEMPERATURES SHOULD RANGE IN THE MID 80S WITHIN THE MTN
VALLEYS TO LOW TO MID 90S EAST. SFC DEWPOINTS ARE FORECAST TO REMAIN
BETWEEN 66 TO 71 DEGREES DURING THE HEAT OF THE AFTERNOON. MODEL
SOUNDINGS AND PLAIN VIEW SHOW CAPES GENERALLY RANGING NEAR 2000
J/KG. NAM AND RAP DCAPE INCREASE TO VALUES GREATER THAN 1000 J/KG
ALONG AND AHEAD OF THE FRONT. BASED ON THE NAM...A BROKEN BAND OF
TSRA SHOULD DEVELOP ALONG AND AHEAD OF THE FRONT. THE CONVECTION MAY
CROSS THE MTNS DURING THE MORNING DAYLIGHT HOURS...SLIDING ACROSS
THE PIEDMONT DURING THE EARLY TO MID AFTERNOON. IN THE WAKE OF THE
BAND...SCT DISCRETE CELLS MAY DEVELOP...MOVING EAST BY SUNSET. GIVEN
THE MODERATE CAPE...A WIDE FIELD OF DCAPE...AND THE DAYTIME PASSAGE
OF A COLD FRONT...IT APPEARS THAT SEVERAL STORMS COULD PRODUCE
DAMAGING WIND GUSTS. HAIL IS POSSIBLE...BUT HIGH WBZ SHOULD LIMIT
HAIL SIZE TO LESS THAN SEVERE. WE WILL HIGHLIGHT THE SEVERE
POTENTIAL IN THE HWO.
TONIGHT...WEAK CAA AND FALLING DEWPOINTS WILL INCREASE FROM NW TO SE
IN THE WAKE OF THE FRONT. SKY COVER SHOULD CLEAR FROM WEST TO
EAST...WITH MOST OF THE AREA UNDER LITTLE CLOUD COVER BY DAWN
FRIDAY. GIVEN THE LIGHT NNW WINDS...THE COOLEST THICKNESSES SHOULD
REMAIN OVER THE MTNS. I WILL FORECAST LOWS IN THE 50S AND 60S ACROSS
THE MTNS...WITH LOW 70S EAST.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM EDT THURSDAY...A BROAD EASTERN TROUGH WILL DEVELOP ON
FRIDAY. UNDER THIS TROUGH...DRIER AIR WILL SPILL INTO THE REGION
FROM THE NORTH AS A DEPARTING SFC FRONT SETTLES TO THE SOUTHEAST
COAST AND SURFACE HIGH PRESSURE STRETCHES FROM THE MID MS RIVER
VALLEY TO THE SRN AND CENTRAL APPALACHIANS. DEWPOINTS
ADVECTING/MIXING WELL DOWN IN THE 50S IN MOST AREAS WILL LARGELY
PRECLUDE ANY CONVECTION ON FRIDAY...WITH ANY ISOLD SHOWERS CONFINED
TO THE EXTREME LOWER PIEDMONT DURING THE AFTERNOON HOURS.
THE EASTERN TROUGH WILL AMPLIFY OVER THE WEEKEND AS A SERIES OF
SHORTWAVES MOVE THROUGH THE MEAN TROUGH AXIS. DRY SFC HIGH PRESSURE
WILL REMAIN IN PLACE ON SATURDAY...WITH A WEAKLY REINFORCING SURFACE
FRONT APPROACHING FROM THE NORTH LATE IN THE DAY. ISOLATED SHOWER OR
WEAK TSTM COVERAGE MAY OCCUR LATE DAY JUST N OF THE REGION ALONG THE
FRONT AND ALSO ACROSS THE SOUTHERN TIER WHERE DEWPOINTS MAY RECOVER
EVER SO SLIGHTLY.
THE AIRMASS WILL CONTINUE TO MODIFY ON SUNDAY...BUT WITH MOISTURE
VERY SLOW TO RETURN. THE SHORTWAVES MOVING THROUGH THE ERN TROUGH
WILL REMAIN DIFFICULT TO TIME...BUT THERE IS DEVELOPING CONSENSUS ON
STRONGER Q VECTOR CONVERGENCE WITH A SHORTWAVE LATE SUNDAY INTO
SUNDAY NIGHT JUST AS MOISTURE REBOUNDS SLIGHTLY. THIS WILL WARRANT
BETTER ISOLD COVERAGE OF SHRA/TSRA LATE SUNDAY...WITH MORE OF A NON
DIURNAL ISOLD NIGHTTIME POP MENTION ON SUNDAY NIGHT. TEMPERATURES
WILL REMAIN NEAR TO SLIGHTLY ABOVE CLIMO THROUGH THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 330 AM EDT THURSDAY...MODEL CONSENSUS DEPICTS SLIGHT
SHALLOWING OF THE ERN TROUGH MONDAY THROUGH WEDNESDAY. MEANWHILE...
A MORE VIGOROUS SURFACE COLD FRONT WILL MOVE SOUTH OF THE GREAT
LAKES ON MONDAY AND APPROACH THE FORECAST AREA FROM THE NORTH ON
TUESDAY. THERE IS CONSIDERABLE MEDIUM RANGE MODEL SPREAD ON HOW FAR
SOUTH THE FRONT GETS...WITH THE ECMWF GENERALLY STALLING THE
BOUNDARY N OF THE AREA...WHILE THE GFS AND ASSOCIATED ENSEMBLES
BRING IT AT LEAST INTO THE NRN TIER BEFORE TURNING IT AROUND AS A
WARM FRONT ON WEDNESDAY. A CONSENSUS APPROACH WILL KEEP THE BOUNDARY
N OF THE AREA BUT FEATURE AN UPTICK IN DIURNAL AFTN CONVECTIVE
COVERAGE AHEAD OF THE FRONT AS THE BOUNDARY LAYER CONTINUES TO
REBOUND AND LAPSE RATES FURTHER STEEPEN ALOFT. TEMPERATURES WILL
GRADUALLY WARM THROUGH THE PERIOD.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
AT KCLT...THE PRIMARY FORECAST CHALLENGE WILL BE THE TIMING OF A
SWEEPING COLD FRONT AND ASSOCIATED WIND SHIFT. AT 6Z...THE COLD
FRONT WAS ANALYZED OVER THE WESTERN OHIO RIVER VALLEY. THE COLD
FRONT IS FORECAST TO SWEEP EAST TODAY...REACHING THE NC PIEDMONT
LATE THIS AFTERNOON. I WILL FORECAST LIGHT SW WINDS ACROSS THE CLT
TERMINAL THROUGH THE EARLY AFTERNOON HOURS...VEERING NW BY 22Z. A
BROKEN BAND OF SHRA/TSRA WILL LIKELY FORM AHEAD OF THE
FRONT...TRACKING SE. BASED ON THE 0Z NAM...THE MOST LIKELY TIME
WINDOW FOR CONVECTION SHOULD OCCUR BETWEEN 17Z TO 21Z...HIGHLIGHTED
WITH A PROB30.
ELSEWHERE...ALL TERMINALS RECEIVED SOME RAINFALL WEDNESDAY AFTERNOON
AND EVENING. TEMPERATURES THROUGH 6Z HAVE REMAIN VERY MILD...KEEPING
DEWPOINT DEPRESSIONS 2 DEGREES OR MORE. HOWEVER...TEMPERATURES
SHOULD CLOSE IN ON CROSSOVER VALUES BY SUNRISE...SUPPORTING A
MENTION OF FOG. I WILL INCLUDE A TEMPO GROUP FOR EACH TERMINAL FOR
DAYBREAK FOG...THICKEST AT KAVL AND KHKY. AFTER SUNRISE...THE
FORECAST CONCERN WILL SHIFT TO THE PASSAGE OF THE COLD FRONT. I WILL
USE A PROB30 FOR EACH SITE...INDICATING A EARLY TO MID AFTERNOON
BAND OF TSRA. AFTER THE CONVECTION...WINDS SHOULD VEER NNW AND
REMAIN THROUGH THE REST OF THE TAF PERIOD.
OUTLOOK...HIGH PRESSURE WITH BUILD IN BEHIND A PASSING COLD FRONT
LATE ON THURSDAY ALLOWING FOR GENERALLY DRY AND QUIET WEATHER
THROUGH THE WEEKEND. CHANCES FOR SHOWERS/THUNDERSTORMS AND THUS
RESTRICTIONS WILL RETURN FOR THE START OF THE NEW WORK WEEK.
CONFIDENCE TABLE...
08-14Z 14-20Z 20-02Z 02-06Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP MED 75% HIGH 100% HIGH 100% HIGH 100%
KAVL MED 65% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 93% MED 79% HIGH 100% HIGH 100%
KGMU HIGH 87% HIGH 100% HIGH 100% HIGH 100%
KAND MED 68% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...NED
SHORT TERM...HG
LONG TERM...HG
AVIATION...NED
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
1154 PM CDT WED JUL 29 2015
.UPDATE...FOR 06Z AVIATION DISCUSSION.
&&
.AVIATION UPDATE...06Z AVIATION DISCUSSION.
SFC FRONT EXPECTED TO MOVE TO NEAR CKV BY 30/06Z AND TO PUSH E OF
CSV 30/12Z-30/14Z. AS SFC FRONT APPROACHES CSV...MVFR CEILING/FOG
FORMATION EXPECTED. MVFR FOG CKV/BNA 30/09Z-30/13Z. BUILDING RIDGING
INFLUENCES SFC/ALOFT SHOULD PROVIDE VFR/SKC CONDITIONS ALL TAF SITES
30/15Z-31/06Z.
&&
.PREV DISCUSSION.../ISSUED 731 PM CDT WED JUL 29 2015/
DISCUSSION...
SYNOPTIC COMPARISONS OF 500 MB HEIGHTS REVEAL MORE OF AN ANTI
CYCLONIC FLOW OVER TN AS COMPARED TO 24 HRS AGO WHEN THE FLOW WAS
STRAIGHT. THIS ADDED EXERTIONS IS WORKING TO IMPEDE THE
CONTINUATION OF THE CONVECTION MOVING SOUTHWARD. SO...AS SFC TEMPS
COOL DOWN...THIS TREND SHOULD CONTINUE. HRRR IS IN SUPPORT OF THE
TREND.
ONLY CHANGE TO FCST WILL BE TO ADJUST POPS SLIGHTLY ACROSS THE
NORTHWEST. HEAT ADVISORY WAS ALLOWED TO EXPIRE AT 7PM.
PREV DISCUSSION... /ISSUED 724 PM CDT WED JUL 29 2015/
UPDATE...FOR 00Z AVIATION DISCUSSION.
AVIATION UPDATE...00Z AVIATION DISCUSSION.
MONITORING A LINE OF SHWRS/TSTMS APPROACHING CKV AROUND 30/00Z...BUT
WEAKENING RAPIDLY. IT LOOKS LIKE AT WORST SOME BKN MVFR CB CEILINGS/VSBYS
CKV...BUT PROBABLY MORE LIKELY VFR CEILINGS...THRU 30/01Z. IF CONVECTION
HOLDS TOGETHER LONG ENOUGH...SOME VCTS MAY BE POSSIBLE AROUND BNA 30/01Z-
30/03Z. AS CONVECTION MOVES SEWD INTO MID STATE...POST BKN/OVC AC/CI
POSSIBLE THRU 30/06Z-30/07Z CKV/BNA. SFC FRONT EXPECTED TO MOVE TO
NEAR CKV BY 30/06Z AND TO PUSH E OF CSV 30/12Z-30/14Z. AS SFC FRONT
APPROACHES CSV...MVFR CEILING/FOG FORMATION EXPECTED. MVFR FOG CKV/BNA
30/08Z-30/14Z. BUILDING RIDGING INFLUENCES SFC/ALOFT SHOULD PROVIDE
VFR/SKC CONDITIONS ALL TAF SITES 30/15Z-30/24Z.
PREV DISCUSSION.../ISSUED 329 PM CDT WED JUL 29 2015/
DISCUSSION...
HOT AND HUMID CONDITIONS CONTINUE ACROSS MIDDLE TENNESSEE THIS
AFTERNOON AS THE SHOWERS AND THUNDERSTORMS THAT MOVED THROUGH THE
AREA EARLIER THIS MORNING LEFT QUITE THE SOUPY AIR MASS IN PLACE.
FOR THIS EVENING AND TONIGHT...STILL THINK A FEW ISOLATED SHOWERS
AND THUNDERSTORMS MAY DEVELOP...BUT WILL SIDE WITH THE HRRR AS MUCH
OF THE AREA WILL REMAIN DRY. A COLD FRONT WILL PUSH ACROSS MIDDLE
TENNESSEE OVERNIGHT BRINGING MUCH DRIER AIR...A VERY NICE CHANGE
IN TIME FOR THE WEEKEND.
THURSDAY THROUGH TUESDAY...A QUIET WEATHER PATTERN CAN BE
EXPECTED...ESPECIALLY FOR THE BEGINNING OF AUGUST...AS HIGH
PRESSURE BUILDS OVER THE REGION. CONDITIONS WILL NOT BE QUITE AS
HUMID ALTHOUGH HIGHS WILL STILL REACH THE LOWER 90S IN MOST
LOCATIONS. BIGGEST DIFFERENCE WILL BE FELT WITH LOW TEMPERATURES
WITH MID TO UPPER 60S EXPECTED INSTEAD OF THE LOWER TO MID 70S.
TEMPERATURES WILL SLOWLY BEGIN TO INCREASE AFTER THE
WEEKEND...ALONG WITH HUMIDITY VALUES TOO.
BY THE MIDDLE OF NEXT WEEK...UPPER LEVEL PATTERN WILL AGAIN SHIFT
TO NORTHWEST FLOW AS THE SURFACE HIGH LOSES ITS STRONGHOLD. AS A
RESULT...THUNDERSTORM CHANCES WILL INCREASE TUESDAY NIGHT AND
LIKELY REMAIN IN THE FORECAST THEREAFTER.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 75 90 66 90 / 30 10 0 0
CLARKSVILLE 71 88 65 89 / 40 0 0 0
CROSSVILLE 72 85 64 84 / 30 20 0 0
COLUMBIA 75 90 66 90 / 20 20 0 0
LAWRENCEBURG 74 90 66 89 / 20 20 0 0
WAVERLY 73 89 67 89 / 30 0 0 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
941 PM CDT FRI JUL 31 2015
.UPDATE...
Expanded isolated thunderstorms into western Permian Basin and
upper trans-Pecos through midnight.
&&
.DISCUSSION...
Isolated showers and thunderstorms continued to develop over the
central and eastern Permian Basin. Outflow boundary pushing into
the Permian Basin from the north may provide additional lift
capable of sustaining at least isolated thunderstorm development
for the next couple of hours. HRRR model suggests that this
activity is likely to wind down shortly after midnight as the
atmosphere stabilizes.
&&
.PREV DISCUSSION... /ISSUED 555 PM CDT FRI JUL 31 2015/
DISCUSSION...
See aviation discussion below.
AVIATION...
VFR conditions are expected the next 24 hours. A weak cool front
across the extreme northern Permian Basin and southeast New Mexico
Plains is forecast to slowly shift south and west overnight toward
the central Permian Basin northwestward toward the Pecos River
near Carlsbad. A few thunderstorms were forming near the Lubbock
area and were generating more boundaries that were pushing into
the northern Permian Basin but these features do not appear like
they will spark significant additional storms overnight that would
impact any of the terminals. Isolated thunderstorms are expected
to develop areawide Saturday with boundaries still lingering but
confidence was not high enough to mention at any of the terminals
at this time. Will continue to monitor. Generally east to southeast
winds of 5 to 15 mph are expected the next 24 hours.
12
PREV DISCUSSION... /ISSUED 213 PM CDT FRI JUL 31 2015/
DISCUSSION...
The center of an upper ridge over the region will shift westward
during the weekend due to an amplifying ua trough over the eastern
U.S., and take up temporary residence near the Four Corners region.
The ridge will be a little weaker as a result, which will allow for
an increase in thunderstorm chances for a few days. Models indicate
a westward moving, but weak, shortwave trough over the Lower Trans
Pecos today which will end up in the vicinity of the Davis
Mountains late this afternoon. This, along with slightly higher
theta e air in these areas, could allow for isolated
thunderstorms there into this evening. The only other locations
which may see convection through the afternoon would be the
northern fringes of the forecast area where higher theta e air
resides. Due to a dry subcloud layer and lack of shear, any storms
could produce gusty winds, frequent lightning, and perhaps brief
heavy rainfall.
Another stronger shortwave trough will translate south/southeastward
around the weakening ua ridge tonight and Saturday, with an outflow
boundary or two at the surface likely moving into the area.
Therefore, will add isolated PoPs over portions of the eastern CWA
tonight, and leave scattered convection already in the forecast for
Saturday. Temperatures will not be quite as hot Saturday, but
should warm back near the century mark most locations outside the
mountains Sunday as the ua ridge begins to expand back eastward.
The ua ridge won`t be as strong as the last few days, and higher
theta e air will linger over portions of the Permian Basin and SE NM
through Sunday, and the higher terrain through early next week.
Will leave slight chances for thunderstorms these areas, but the
general trend through early next week will be for mainly dry
conditions and temperatures staying several degrees above normal.
&&
.PRELIMINARY POINT TEMPS/POPS...
BIG SPRING TX 74 95 75 98 / 20 30 20 30
CARLSBAD NM 73 98 70 99 / 10 10 20 10
DRYDEN TX 76 100 75 101 / 20 20 10 10
FORT STOCKTON TX 72 95 73 98 / 10 10 10 10
GUADALUPE PASS TX 69 88 69 91 / 10 10 20 20
HOBBS NM 68 94 69 95 / 20 20 20 10
MARFA TX 61 89 63 89 / 10 20 20 20
MIDLAND INTL AIRPORT TX 74 97 74 99 / 10 20 10 20
ODESSA TX 75 97 75 98 / 10 20 10 20
WINK TX 75 100 74 101 / 10 10 10 10
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
99/05
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
654 PM CDT FRI JUL 31 2015
.DISCUSSION...DID A QUICK UPDATE EARLIER FOR INCREASING RAIN
CHANCES EARLY THIS EVENING BASED ON RADAR ACTIVITY...WHICH SHOULD
WANE IN ANOTHER HOUR OR TWO. WILL UPDATE AGAIN WHEN ACTIVITY WANES
AND ADJUST OTHER DATA ACCORDINGLY.
SEE 00Z AVIATION DISCUSSION.
&&
.AVIATION...DO HAVE SOME REMNANT CONVECTION WHICH MAY IMPACT ALL
BUT KVCT (VCSH) FOR ANOTHER HOUR OR TWO OR THREE THEN BE OVER
(TEMPOS TIL 02/03Z). AFTER THAT...EXPECT MVFR CONDITIONS WITH
LIGHT WINDS...MAYBE SOME 5SM-6SM BR AOA 10Z AT KALI AND/OR KVCT
BUT BFR 14Z WITH WINDS LIGHT AND VARIABLE. WINDS GENERALLY REMAIN
LIGHT (MAINLY NORTH OR NORTHEAST) IN THE MORNING THEN BECOME EAST
IN THE AFTERNOON GENERALLY LESS THAN 11 KNOTS AS SEA BREEZE KICKS
IN JUST A BIT BUT WITH A WARM DAY ON SATURDAY NOT EXPECTING A
STRONG SEA-BREEZE. WITH MUCH DRIER AIR COMING IN ON SATURDAY
DURING THE DAY...AM NOT EXPECTING ANY CONVECTION LIKE WE ARE
SEEING TODAY.
&&
.PREV DISCUSSION... /ISSUED 309 PM CDT FRI JUL 31 2015/
SHORT TERM (TONIGHT THROUGH SATURDAY NIGHT)...HAVE FINALLY
DEVELOPED SOME ISOLATED TO SCATTERED SHOWERS AND A FEW
THUNDERSTORMS ACROSS THE AREA THIS AFTERNOON. HRRR MODEL HANDLING
THIS REASONABLY WELL...ENDS MOST OF THE ACTIVITY BY ABOUT 02Z. HAVE
20 POPS AREA WIDE FOR THE EVENING...WITH 10S AND 20S AFTER
MIDNIGHT. GLOBAL MODELS CONTINUE TO STRUGGLE WITH QPF...GFS
DEFINITELY STILL TOO AGGRESSIVE. SOMETHING OF A MIX BETWEEN NAM
AND ECMWF APPEARS THE BEST. THAT SAID...BOTH OF THOSE MODELS ARE
QUIET ON SATURDAY...EXCEPT IN MARINE AREA. HAVE CUT POPS FOR
INLAND AREAS IN THE MORNING...BUT WILL LEAVE A 20 POP AREA WIDE
FOR THE AFTERNOON AS HIGH MOISTURE AIR WILL STILL BE IN PLACE AND
COULD GET SOME SHOWERS TO POP UP ONCE AGAIN.
WITH NO MAJOR PATTERN CHANCE...EXPECT TEMPERATURES TOMORROW TO
APPROACH THE SAME VALUES WE/RE SEEING TODAY AS WE SHOULD KEEP A
LIGHT AND VARIABLE WIND...NOT THE ONSHORE FLOW WE ARE USED TO THIS
TIME OF YEAR. HAVE HIGHS MAINLY IN THE UPPER 90S TO AROUND 100
ACROSS THE AREA. HEAT INDEX VALUES WILL BE AT LEAST BETWEEN 100
AND 105...BUT COULD BE 105 TO 109 IF WE DON`T MIX OUT THE NEAR
SURFACE MOISTURE.
LONG TERM (SUNDAY THROUGH FRIDAY)...EXTENDED FORECAST LOOKS
RELATIVELY STRAIGHTFORWARD WITH UPPER RIDGE AXIS REPOSITIONING
ITSELF OVER THE SOUTHERN PLAINS AND SURFACE LEE DEVELOPMENT
GENERATING TYPICAL ONSHORE FLOW REGIME ACROSS THE COASTAL BEND. ANY
LINGERING PRECIPITATION CHANCES WITH A DECAYING BOUNDARY ON SUNDAY
SHOULD BE CONFINED TO OFFSHORE ZONES...THEN A DRY FORECAST THROUGH
THE WEEK.
TEMPERATURES WILL REMAIN A CATEGORY OR SO ABOVE NORMAL THROUGH THE
PERIOD. HEAT INDEX LEVELS WILL FLIRT WITH SPS CRITERIA ON A DAILY
BASIS...THOUGH ACTUAL ADVISORY CRITERIA HEAT APPEARS UNLIKELY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 76 98 76 96 77 / 40 20 10 10 10
VICTORIA 74 100 74 98 75 / 30 20 10 10 10
LAREDO 78 103 78 103 78 / 30 20 10 10 0
ALICE 75 100 75 98 75 / 40 20 10 10 10
ROCKPORT 76 95 79 91 80 / 40 20 10 10 10
COTULLA 77 102 75 103 76 / 30 20 10 0 0
KINGSVILLE 75 99 76 98 76 / 40 20 10 10 10
NAVY CORPUS 78 92 79 90 80 / 40 20 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
GW/86...SHORT TERM
GW/86...LONG TERM
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
142 PM CDT THU JUL 30 2015
.SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
A VERY ISOLATED SHOT AT THUNDERSTORMS WILL BE POSSIBLE TONIGHT AS
ENERGY AND MOISTURE WILL BE MOVING IN FROM THE EAST DUE TO A COLD
FRONT PROGRESSING SOUTHWARD ACROSS THE SE CONUS. WITH THE UPPER
LEVEL STEERING WINDS BEING NORTHEAST AND EAST...SOME OF THE SHOWER
AND STORM DEVELOPMENT IN THE HI RES MODELS COULD MAKE IT AS FAR
WEST AS THE EASTERN PERIPHERY OF THE CWA. HOWEVER...AN APPRECIABLE
MOISTURE GRADIENT OVER BASICALLY THE I35 CORRIDOR SHOULD PREVENT
MUCH FROM GETTING ANY FARTHER WESTWARD. ALSO...DRY LOW LEVEL
CONDITIONS AS SEEN ON LAPS AND RUC SOUNDINGS WOULD CHALLENGE ANY
PRECIPITATION FROM REACHING THE SURFACE SO CONFIDENCE IS NOT HIGH
FOR MEASURABLE PRECIP THIS EVENING. THEREFORE LEFT THE ISOLATED
MENTION IN FOR THE EASTERNMOST AREAS OF THE CWA.
SHOULD SEE SOME SCATTERED LOW CLOUD DEVELOPMENT IN THE MORNING BUT
LESS THAN NORMAL WITH LIGHT AND VARIABLE WINDS. THE LIGHT WINDS
AND MOSTLY UNOBSTRUCTED SKY SHOULD KEEP LOWS A COUPLE DEGREES
BELOW GUIDANCE AS THEY WERE THIS MORNING.
BEST SHOT AT MEASURABLE PRECIP WILL BE IN THE AFTERNOON FRIDAY AS
THE CONTINUING WEST COLD FRONT INTERACTS WITH THE COASTAL PLAINS
SEA BREEZE. AN AREA OF ENHANCED QPF WAS NOTED IN THE NAM AND GFS
WHICH MAKES SENSE AS AN AREA OF LIFT ENOUGH TO REALIZE DECENT
INSTABILITY DURING THE AFTERNOON HOURS. STILL THINK PWATS ARE A
BIT EXAGGERATED IN THE FORECAST SOUNDINGS BUT STILL THINK A
BRIEFLY HEAVY DOWNPOUR AND GUSTY WINDS ARE STILL IN PLAY TOMORROW
AFTERNOON.
&&
.LONG TERM (SATURDAY THROUGH THURSDAY)...
MODELS ARE TRENDING A BIT DRIER OVER THE WEEKEND BUT WITH THE BEST
OPPORTUNITY FOR SOUTH CENTRAL TEXAS TO RECEIVE RAINFALL BEING
SATURDAY AS A FORECAST COMPLEX DEVELOPS IN THE PANHANDLE AND
NORTHERLY UPPER LEVEL FLOW CARRIES IT SOUTHWARD. UNSURE ABOUT HOW
FAR SOUTH THIS WILL BE ABLE TO MAKE IT BUT CONDITIONS ARE
FAVORABLE FOR A WELL SUSTAINED COLD POOL SHOULD AN ORGANIZED
SYSTEM DEVELOP. THEREFORE HIGHLIGHTED THE NORTHERN PERIPHERY OF
THE CWA ON THE PLATEAU FOR THE BEST SHOT AT RAINFALL SATURDAY.
AFTERWARDS...THE UPPER LEVEL PATTERN RETURNS TO THE SUMMER
DOLDRUMS OF HOT AND DRY THROUGH THE END OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 76 100 76 100 76 / 10 30 20 20 0
AUSTIN BERGSTROM INTL AIRPORT 72 99 74 99 73 / 10 30 20 20 0
NEW BRAUNFELS MUNI AIRPORT 74 101 76 100 74 / 10 30 20 20 10
BURNET MUNI AIRPORT 74 99 75 98 74 / 10 30 20 20 -
DEL RIO INTL AIRPORT 75 101 78 101 78 / - 10 20 20 10
GEORGETOWN MUNI AIRPORT 74 100 75 98 74 / 10 30 20 20 0
HONDO MUNI AIRPORT 71 98 76 100 75 / 10 30 20 20 10
SAN MARCOS MUNI AIRPORT 75 98 76 99 75 / 10 30 20 20 10
LA GRANGE - FAYETTE REGIONAL 76 99 76 99 75 / 20 30 20 10 10
SAN ANTONIO INTL AIRPORT 76 99 78 99 77 / 10 30 20 20 10
STINSON MUNI AIRPORT 74 100 77 100 76 / 10 30 20 20 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...04
SYNOPTIC/GRIDS...TB3
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1248 PM CDT THU JUL 30 2015
.DISCUSSION...
PLEASE SEE 18Z AVIATION DISCUSSION...
&&
.AVIATION...
VFR CONDITIONS TO PREVAIL FOR THE NEXT 24 HOURS. A FEW ISOLATED
SHOWERS ARE POSSIBLE THIS AFTERNOON MOSTLY TO THE EAST OF HIGHWAY
59. DROPPED MENTION OF TSRA IN TAFS BECAUSE STRONG SUBSIDENCE
OVER THE AREA IS LIMITING CONVECTION. WINDS WILL BE FROM THE N-NE
AT 5 TO 10 KNOTS. 44
&&
.PREV DISCUSSION... /ISSUED 904 AM CDT THU JUL 30 2015/
DISCUSSION...
SEEING MORE CLOUD COVER ACROSS EASTERN AREAS THIS AM AS DEEPER
MOISTURE ADVECTS IN FROM THE EAST. QUITE A DIFFERENCE
BETWEEN THE 12Z LCH AND CRP SOUNDINGS (2.2 VS. 1.5 INCH
PRECIPITABLE WATER). GIVEN THIS DEEPER MOISTURE ACROSS EASTERN
AREAS...AND THE LATEST HRRR REFLECTIVITY FORECAST...BELIEVE THAT
THE CHC POP ACROSS THE EAST AND SLIGHT CHC POP ACROSS THE WEST IS
ON TRACK FOR THIS AFT/EVE. MAX TEMPS NEAR 100 INLAND AND LOWER TO
MID 90S COAST APPEARS ON TRACK AS WELL. NO SIGNIFICANT CHGS TO
THE ONGOING FCST. 33
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 78 99 76 101 76 / 20 30 10 10 10
HOUSTON (IAH) 78 98 76 100 76 / 30 30 20 20 10
GALVESTON (GLS) 82 92 81 92 82 / 30 30 20 20 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...33
AVIATION/MARINE...44
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1241 PM CDT THU JUL 30 2015
.AVIATION... /FOR THE 18Z TAFS/
MVFR CEILINGS WILL LINGER FOR AT LEAST A COUPLE MORE HOURS AT
KGUY...OTHERWISE VFR CONDITIONS HAVE RETURNED AT KDHT AND KAMA.
ISOLATED TO SCATTERED THUNDERSTORMS SHOULD DEVELOP WITH DIURNAL
DESTABILIZATION BY LATE AFTERNOON OR EARLY EVENING BUT PROBABILITY OF
EITHER OF THE THREE TERMINALS BEING IMPACTED IS LOW UNTIL MORE
ORGANIZED THUNDERSTORM COMPLEX DEVELOPS LATER THIS EVENING. ALTHOUGH
SOMEWHAT CONDITIONAL...CURRENT FORECAST IS FOR A PERIOD OF
THUNDERSTORMS BEGINNING MID EVENING AND LASTING FOR A FEW HOURS
BEFORE PROBABILITIES DECREASE NECESSITATING A PROB30 GROUP THROUGH
EARLY MORNING. WINDS TOMORROW MORNING ARE ALSO CONDITIONAL ON
THUNDERSTORM COMPLEX DEVELOPMENT AND ARE MORE NORTHWESTERLY THAN
CURRENT GUIDANCE INDICATES. AMENDMENTS WILL PROBABLY BE NEEDED
THROUGH THE EVENING.
BRB
&&
.PREV DISCUSSION... /ISSUED 406 AM CDT THU JUL 30 2015/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT...
SHOWERS AND THUNDERSTORMS ARE STARTING OUT THIS MORNING BY FORMING
ALONG A LINE FROM NARA VISA TO HARTLEY TO BEAVER...WHICH IS A SIMILAR
PATH TO THE STORMS THAT DROPPED PRECIP TUESDAY. THE HRRR SHOWS THESE
STORMS CONTINUING TO BUILD ACROSS THE NORTH TEXAS PANHANDLE AND DIE
OFF AROUND MID AFTERNOON. RADAR ESTIMATES SHOW PRECIP TOTALS OF
ANYWHERE FROM ONE TO THREE INCHES UNDER THE STRONGER STORMS.
CONSIDERING PW VALUES ARE STILL ABOVE 2 STANDARD DEVIATIONS AND THE
SLOW MOVING NATURE OF THESE STORMS...ONLY 15 MPH...FLOODING WILL BE
THE BIG CONCERN.
AS AN UPPER LEVEL SHORT WAVE TROUGH CROSSES THE
NORTHERN TEXAS PANHANDLE AND OKLAHOMA PANHANDLE TODAY...MORE RAIN
CHANCES CAN BE EXPECTED FOR THIS AREA THROUGH THE NIGHT. BY FRIDAY
NORTHWEST FLOW TAKES OVER AS THE HIGH WILL BE IN PLACE OVER THE FOUR
CORNERS. THIS WILL BRING THE OKLAHOMA PANHANDLE AND THE NORTHERN
HALF OF THE TEXAS PANHANDLE ANOTHER CHANCE FOR STORMS AS THEY COME
OFF THE MOUNTAINS IN NEW MEXICO AND COLORADO. MODELS SEEM TO BE IN
BETTER AGREEMENT AND SHOW A BETTER CHANCE ON SATURDAY FOR MORE
WIDESPREAD STORMS TO FORM SO BUMPED UP POPS A BIT. WITH THE
CONTINUATION OF CLOUDS ACROSS THE AREA...THE TEMPS WILL REMAIN
COOLER IN THE UPPER 80S AND LOW 90S.
MB
LONG TERM...SUNDAY THROUGH NEXT THURSDAY
NOT MUCH CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR SUNDAY ONWARD
THROUGH THE MIDDLE OF NEXT WEEK FOR THE PANHANDLES. THE RIDGE CENTER
WILL REMAIN OVER NEW MEXICO TO KEEP THE PANHANDLES IN NORTHWEST FLOW.
EMBEDDED SHORTWAVES SHOULD KEEP OFF AND ON RAIN CHANCES IN THE
FORECAST DURING THE EXTENDED PERIODS. THE ECMWF DOES HINT AT THE
POSSIBILITY OF THE RIDGE SLIDING A LITTLE FURTHER SOUTH COMPARED TO
THE GFS. THE FURTHER SOUTHERN POSITION COULD ALLOW FOR POSSIBLY FEWER
PRECIP ROUNDS COMPARED TO THE GFS, BUT THIS WOULD OPEN THE PANHANDLES
UP TO POSSIBLY MORE INTENSE ROUNDS OF RAIN GIVEN BETTER DYNAMICS.
FURTHER ADJUSTMENTS TO THE POP STRUCTURE WILL BE POSSIBLE IN FUTURE
FORECAST PACKAGES AS MODELS GET A BETTER HANDLE ON THE POSITION OF
THE UPPER RIDGE.
CM
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
17/15
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1023 AM CDT THU JUL 30 2015
.UPDATE...
HAVE MADE UPDATES THIS MORNING TO INCREASE TEMPORAL RESOLUTION AND
ADD SPATIAL DETAIL TO POP AND WEATHER GRIDS. ALSO ADJUSTED WINDS
BASED ON CURRENT TRENDS. LATEST RADAR TRENDS SHOW AN INCREASING
CONVECTION IN THE NORTHEAST. THIS SEEMS TO BE OCCURRING DUE TO WEAK
BROAD ISENTROPIC ASCENT ATOP SHALLOW OUTFLOW FROM EARLIER CONVECTION
THAT OCCURRED IN THE NORTHWEST. SATELLITE DERIVED PWAT INDICATE
VALUES RANGING FROM AROUND 1.5 INCHES ACROSS THE NORTHERN AND CENTRAL
PORTIONS OF THE FORECAST AREA (AND THIS MATCHES UP WELL WITH 12Z KAMA
SOUNDING) TO NEARLY 2 INCHES IN THE NORTHEAST. GIVEN MOIST LOW LEVELS
AM CONCERNED ABOUT LOCALIZED AREAL FLOODING MAINLY IN THE NORTHEAST
IF MORE WIDESPREAD CONVECTION CAN PERSIST INTO THE AFTERNOON. WILL
CONTINUE TO MONITOR TRENDS.
BRB
&&
.PREV DISCUSSION... /ISSUED 406 AM CDT THU JUL 30 2015/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT...
SHOWERS AND THUNDERSTORMS ARE STARTING OUT THIS MORNING BY FORMING
ALONG A LINE FROM NARA VISA TO HARTLEY TO BEAVER...WHICH IS A SIMILAR
PATH TO THE STORMS THAT DROPPED PRECIP TUESDAY. THE HRRR SHOWS THESE
STORMS CONTINUING TO BUILD ACROSS THE NORTH TEXAS PANHANDLE AND DIE
OFF AROUND MID AFTERNOON. RADAR ESTIMATES SHOW PRECIP TOTALS OF
ANYWHERE FROM ONE TO THREE INCHES UNDER THE STRONGER STORMS.
CONSIDERING PW VALUES ARE STILL ABOVE 2 STANDARD DEVIATIONS AND THE
SLOW MOVING NATURE OF THESE STORMS...ONLY 15 MPH...FLOODING WILL BE
THE BIG CONCERN.
AS AN UPPER LEVEL SHORT WAVE TROUGH CROSSES THE
NORTHERN TEXAS PANHANDLE AND OKLAHOMA PANHANDLE TODAY...MORE RAIN
CHANCES CAN BE EXPECTED FOR THIS AREA THROUGH THE NIGHT. BY FRIDAY
NORTHWEST FLOW TAKES OVER AS THE HIGH WILL BE IN PLACE OVER THE FOUR
CORNERS. THIS WILL BRING THE OKLAHOMA PANHANDLE AND THE NORTHERN
HALF OF THE TEXAS PANHANDLE ANOTHER CHANCE FOR STORMS AS THEY COME
OFF THE MOUNTAINS IN NEW MEXICO AND COLORADO. MODELS SEEM TO BE IN
BETTER AGREEMENT AND SHOW A BETTER CHANCE ON SATURDAY FOR MORE
WIDESPREAD STORMS TO FORM SO BUMPED UP POPS A BIT. WITH THE
CONTINUATION OF CLOUDS ACROSS THE AREA...THE TEMPS WILL REMAIN
COOLER IN THE UPPER 80S AND LOW 90S.
MB
LONG TERM...SUNDAY THROUGH NEXT THURSDAY
NOT MUCH CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR SUNDAY ONWARD
THROUGH THE MIDDLE OF NEXT WEEK FOR THE PANHANDLES. THE RIDGE CENTER
WILL REMAIN OVER NEW MEXICO TO KEEP THE PANHANDLES IN NORTHWEST FLOW.
EMBEDDED SHORTWAVES SHOULD KEEP OFF AND ON RAIN CHANCES IN THE
FORECAST DURING THE EXTENDED PERIODS. THE ECMWF DOES HINT AT THE
POSSIBILITY OF THE RIDGE SLIDING A LITTLE FURTHER SOUTH COMPARED TO
THE GFS. THE FURTHER SOUTHERN POSITION COULD ALLOW FOR POSSIBLY FEWER
PRECIP ROUNDS COMPARED TO THE GFS, BUT THIS WOULD OPEN THE PANHANDLES
UP TO POSSIBLY MORE INTENSE ROUNDS OF RAIN GIVEN BETTER DYNAMICS.
FURTHER ADJUSTMENTS TO THE POP STRUCTURE WILL BE POSSIBLE IN FUTURE
FORECAST PACKAGES AS MODELS GET A BETTER HANDLE ON THE POSITION OF
THE UPPER RIDGE.
CM
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
17/15
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
904 AM CDT THU JUL 30 2015
.DISCUSSION...
SEEING MORE CLOUD COVER ACROSS EASTERN AREAS THIS AM AS DEEPER
MOISTURE ADVECTS IN FROM THE EAST. QUITE A DIFFERENCE
BETWEEN THE 12Z LCH AND CRP SOUNDINGS (2.2 VS. 1.5 INCH
PRECIPITABLE WATER). GIVEN THIS DEEPER MOISTURE ACROSS EASTERN
AREAS...AND THE LATEST HRRR REFLECTIVITY FORECAST...BELIEVE THAT
THE CHC POP ACROSS THE EAST AND SLIGHT CHC POP ACROSS THE WEST IS
ON TRACK FOR THIS AFT/EVE. MAX TEMPS NEAR 100 INLAND AND LOWER TO
MID 90S COAST APPEARS ON TRACK AS WELL. NO SIGNIFICANT CHGS TO
THE ONGOING FCST. 33
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 99 78 99 76 101 / 10 20 30 10 10
HOUSTON (IAH) 99 78 98 76 100 / 30 30 30 20 20
GALVESTON (GLS) 92 82 92 81 92 / 30 30 30 20 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...33
AREA FORECAST DISCUSSION
NWS AMARILLO TX
635 AM CDT THU JUL 30 2015
.AVIATION...
12Z TAFS... WIDESPREAD MVFR/IFR CONDITIONS THIS MORNING ACROSS THE
PANHANDLES. MEDIUM CONFIDENCE IN CIGS SLOWLY IMPROVING TO MVFR/LOW END
VFR MID TO LATE MORNING. SCATTERED CONVECTION IS POSSIBLE ACROSS THE
OKLAHOMA AND WESTERN TEXAS PANHANDLES THIS MORNING...AND DEVELOPING
AGAIN LATER THIS AFTERNOON AND EVENING ACROSS MUCH OF THE AREA. WINDS
WILL BE MOSTLY FROM THE NORTHEAST TO EAST AND BECOMING SOUTHEASTERLY
THIS AFTERNOON AT 5 TO 12KTS.
ELSENHEIMER
&&
.PREV DISCUSSION... /ISSUED 406 AM CDT THU JUL 30 2015/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT...
SHOWERS AND THUNDERSTORMS ARE STARTING OUT THIS MORNING BY FORMING
ALONG A LINE FROM NARA VISA TO HARTLEY TO BEAVER...WHICH IS A SIMILAR
PATH TO THE STORMS THAT DROPPED PRECIP TUESDAY. THE HRRR SHOWS THESE
STORMS CONTINUING TO BUILD ACROSS THE NORTH TEXAS PANHANDLE AND DIE
OFF AROUND MID AFTERNOON. RADAR ESTIMATES SHOW PRECIP TOTALS OF
ANYWHERE FROM ONE TO THREE INCHES UNDER THE STRONGER STORMS.
CONSIDERING PW VALUES ARE STILL ABOVE 2 STANDARD DEVIATIONS AND THE
SLOW MOVING NATURE OF THESE STORMS...ONLY 15 MPH...FLOODING WILL BE
THE BIG CONCERN.
AS AN UPPER LEVEL SHORT WAVE TROUGH CROSSES THE
NORTHERN TEXAS PANHANDLE AND OKLAHOMA PANHANDLE TODAY...MORE RAIN
CHANCES CAN BE EXPECTED FOR THIS AREA THROUGH THE NIGHT. BY FRIDAY
NORTHWEST FLOW TAKES OVER AS THE HIGH WILL BE IN PLACE OVER THE FOUR
CORNERS. THIS WILL BRING THE OKLAHOMA PANHANDLE AND THE NORTHERN
HALF OF THE TEXAS PANHANDLE ANOTHER CHANCE FOR STORMS AS THEY COME
OFF THE MOUNTAINS IN NEW MEXICO AND COLORADO. MODELS SEEM TO BE IN
BETTER AGREEMENT AND SHOW A BETTER CHANCE ON SATURDAY FOR MORE
WIDESPREAD STORMS TO FORM SO BUMPED UP POPS A BIT. WITH THE
CONTINUATION OF CLOUDS ACROSS THE AREA...THE TEMPS WILL REMAIN
COOLER IN THE UPPER 80S AND LOW 90S.
MB
LONG TERM...SUNDAY THROUGH NEXT THURSDAY
NOT MUCH CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR SUNDAY ONWARD
THROUGH THE MIDDLE OF NEXT WEEK FOR THE PANHANDLES. THE RIDGE CENTER
WILL REMAIN OVER NEW MEXICO TO KEEP THE PANHANDLES IN NORTHWEST FLOW.
EMBEDDED SHORTWAVES SHOULD KEEP OFF AND ON RAIN CHANCES IN THE
FORECAST DURING THE EXTENDED PERIODS. THE ECMWF DOES HINT AT THE
POSSIBILITY OF THE RIDGE SLIDING A LITTLE FURTHER SOUTH COMPARED TO
THE GFS. THE FURTHER SOUTHERN POSITION COULD ALLOW FOR POSSIBLY FEWER
PRECIP ROUNDS COMPARED TO THE GFS, BUT THIS WOULD OPEN THE PANHANDLES
UP TO POSSIBLY MORE INTENSE ROUNDS OF RAIN GIVEN BETTER DYNAMICS.
FURTHER ADJUSTMENTS TO THE POP STRUCTURE WILL BE POSSIBLE IN FUTURE
FORECAST PACKAGES AS MODELS GET A BETTER HANDLE ON THE POSITION OF
THE UPPER RIDGE.
CM
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
18/14
AREA FORECAST DISCUSSION
NWS AMARILLO TX
406 AM CDT THU JUL 30 2015
.SHORT TERM...TODAY THROUGH SATURDAY NIGHT...
SHOWERS AND THUNDERSTORMS ARE STARTING OUT THIS MORNING BY FORMING
ALONG A LINE FROM NARA VISA TO HARTLEY TO BEAVER...WHICH IS A SIMILAR
PATH TO THE STORMS THAT DROPPED PRECIP TUESDAY. THE HRRR SHOWS THESE
STORMS CONTINUING TO BUILD ACROSS THE NORTH TEXAS PANHANDLE AND DIE
OFF AROUND MID AFTERNOON. RADAR ESTIMATES SHOW PRECIP TOTALS OF
ANYWHERE FROM ONE TO THREE INCHES UNDER THE STRONGER STORMS.
CONSIDERING PW VALUES ARE STILL ABOVE 2 STANDARD DEVIATIONS AND THE
SLOW MOVING NATURE OF THESE STORMS...ONLY 15 MPH...FLOODING WILL BE
THE BIG CONCERN.
AS AN UPPER LEVEL SHORT WAVE TROUGH CROSSES THE
NORTHERN TEXAS PANHANDLE AND OKLAHOMA PANHANDLE TODAY...MORE RAIN
CHANCES CAN BE EXPECTED FOR THIS AREA THROUGH THE NIGHT. BY FRIDAY
NORTHWEST FLOW TAKES OVER AS THE HIGH WILL BE IN PLACE OVER THE FOUR
CORNERS. THIS WILL BRING THE OKLAHOMA PANHANDLE AND THE NORTHERN
HALF OF THE TEXAS PANHANDLE ANOTHER CHANCE FOR STORMS AS THEY COME
OFF THE MOUNTAINS IN NEW MEXICO AND COLORADO. MODELS SEEM TO BE IN
BETTER AGREEMENT AND SHOW A BETTER CHANCE ON SATURDAY FOR MORE
WIDESPREAD STORMS TO FORM SO BUMPED UP POPS A BIT. WITH THE
CONTINUATION OF CLOUDS ACROSS THE AREA...THE TEMPS WILL REMAIN
COOLER IN THE UPPER 80S AND LOW 90S.
MB
.LONG TERM...SUNDAY THROUGH NEXT THURSDAY
NOT MUCH CHANGE IN THE OVERALL UPPER LEVEL PATTERN FOR SUNDAY ONWARD
THROUGH THE MIDDLE OF NEXT WEEK FOR THE PANHANDLES. THE RIDGE CENTER
WILL REMAIN OVER NEW MEXICO TO KEEP THE PANHANDLES IN NORTHWEST FLOW.
EMBEDDED SHORTWAVES SHOULD KEEP OFF AND ON RAIN CHANCES IN THE
FORECAST DURING THE EXTENDED PERIODS. THE ECMWF DOES HINT AT THE
POSSIBILITY OF THE RIDGE SLIDING A LITTLE FURTHER SOUTH COMPARED TO
THE GFS. THE FURTHER SOUTHERN POSITION COULD ALLOW FOR POSSIBLY FEWER
PRECIP ROUNDS COMPARED TO THE GFS, BUT THIS WOULD OPEN THE PANHANDLES
UP TO POSSIBLY MORE INTENSE ROUNDS OF RAIN GIVEN BETTER DYNAMICS.
FURTHER ADJUSTMENTS TO THE POP STRUCTURE WILL BE POSSIBLE IN FUTURE
FORECAST PACKAGES AS MODELS GET A BETTER HANDLE ON THE POSITION OF
THE UPPER RIDGE.
CM
&&
.PRELIMINARY POINT TEMPS/POPS...
AMARILLO TX 85 67 85 68 86 / 20 20 20 30 40
BEAVER OK 86 68 87 69 88 / 30 30 30 20 30
BOISE CITY OK 84 64 86 66 85 / 40 40 30 30 30
BORGER TX 87 70 87 70 89 / 20 30 30 30 40
BOYS RANCH TX 83 65 83 66 85 / 20 30 20 30 30
CANYON TX 87 67 87 68 87 / 20 20 20 20 40
CLARENDON TX 90 70 88 70 88 / 20 20 20 30 30
DALHART TX 88 66 88 67 87 / 30 40 30 40 40
GUYMON OK 87 67 88 68 87 / 30 40 30 30 30
HEREFORD TX 85 67 87 67 89 / 20 20 30 30 30
LIPSCOMB TX 87 69 88 70 87 / 30 30 30 20 30
PAMPA TX 85 66 85 68 85 / 20 30 30 30 30
SHAMROCK TX 90 69 87 71 88 / 20 30 30 30 30
WELLINGTON TX 92 71 90 72 90 / 20 20 30 30 30
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
18/16
AREA FORECAST DISCUSSION
NWS MIDLAND/ODESSA TX
1254 AM CDT THU JUL 30 2015
DISCUSSION...
See 06Z Aviation Discussion below.
AVIATION...
Area radars and short-term models show convection has largely
diminished across the area. VFR conditions will prevail next 24
hours in return flow under persistent ridging aloft. Forecast
soundings develop a widespread cu field by late Thursday morning,
w/initial bases 4.5-7 kft agl.
PREV DISCUSSION... /ISSUED 332 PM CDT WED JUL 29 2015/
UPDATE...
Updated forecast for increased chance of thunderstorms over the
northern Permian Basin, southeast New Mexico and mountain areas.
DISCUSSION...
By mid-afternoon, showers and thunderstorms were developing along
a surface boundary entering the northern Permian Basin in an area
characterized by CAPE values ranging from 500 to 1000. Continued
development along this boundary as well as any additional outflow
boundaries that might develop is possible through early evening as
the atmosphere across the region is uncapped. Though instability
is less over the Permian Basin, will need to watch boundaries for
possible foci of development. Thunderstorms will begin to
decrease this evening with a loss of heating. Though shear is
insufficient for organized thunderstorm activity, DCAPE values are
significant, in excess of 1000. Sub-cloud evaporation will be
capable of producing strong and possibly damaging downbursts.
PREV DISCUSSION... /ISSUED 224 PM CDT WED JUL 29 2015/
DISCUSSION...As of 2:15 PM CDT Wednesday...Hot and muggy weather
continues with convection starting in the usual places...the
Davis/Guadalupe Mtns and the adjacent Plains. Convection is also
forming a little further east in Western Lea and Eddy Counties
along the thetae ridge per the HRRR and RAP13 high res models.
The persistent subtropical ridge centered over the Arklatex area
will shift west over the Central Plains as a trough deepens in the
eastern US. This might actually result in no convection in the
CWA Thursday thru Friday due to increased subsidence from the
ridge center moving overhead. Temps might not be as hot as the
previous week...but will remain above normal.
Medium range models are hinting at the possibility of convection
in the CWA over the weekend as the ridge continues to shift west
to over the four corners area. This will bring a NW flow aloft
possibly bringing convection into the area out of Northern New
Mexico.
As a trough in the EastPac moves into the Pacific NW early next
week the ridge will flatten and elongate bringing a return to
drier weather...with triple digits possible once again in the
Plains by mid week.
Strobin
&&
.MAF WATCHES/WARNINGS/ADVISORIES...
NM...NONE.
TX...NONE.
&&
$$
44
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
310 PM EDT THU JUL 30 2015
.SYNOPSIS...
A COLD FRONT WILL SLIDE EAST ACROSS OUR REGION TONIGHT...STALLING
ALONG THE SOUTHEAST COAST FRIDAY INTO SATURDAY. THIS WILL ALLOW
FOR HIGH PRESSURE TO KEEP MOST OF THE AREA DRY THROUGH THE
WEEKEND...AS IT MOVES IN FROM THE WEST.
&&
.NEAR TERM /THROUGH FRIDAY/...
AS OF 310 PM EDT THURSDAY...
SCATTERED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED IN THE UNSTABLE
AIR AHEAD AND ALONG THE COLD FRONT THIS AFTERNOON. THE STORM
PREDICTION CENTER IN THEIR DAY 1 CONVECTIVE OUTLOOK HAS REMOVED THE
MARGINAL RISK AREAS FROM OUR COUNTY WARNING AREA...LEAVING US IN THE
GENERAL THUNDERSTORM AREA. THE COLD FRONT ALONG THE MOUNTAINS
THIS AFTERNOON WILL MOVE EAST THIS EVENING INTO TONIGHT. LOOKING
AT THE LATEST SPC MESOSCALE ANALYSIS...THE RICHEST CAPES AROUND 2K
J/KG AND SFC BASED LIS AROUND MINUS 5 WHERE EAST OF THE BLUE RIDGE
MOUNTAINS. HOWEVER...THE BEST DYNAMICS AND MOISTURE CONVERGENCE
WILL REMAIN NORTH OF OUR AREA. LEANED POPS THIS AFTERNOON INTO
TONIGHT TOWARDS THE LATEST HRRR WITH JUST A SLIGHTLY SLOWER TIMING
AND KEPT THE HIGHEST CHANCES IN THE EAST.
DRIER AIR OVERSPREADING OUR WESTERN CWA TONIGHT...WHILE THE FRONT
SLOWS DOWN IN THE EAST AND KEEPS THE HIGHER DEWPOINTS LINGERING
LONGER. SHOWERS AND THUNDERSTORMS SHOULD MOVE OUT OF THE PIEDMONT BY
MIDNIGHT...WITH SKIES CLEARING. LIGHT WINDS AND LOW LEVEL MOISTURE
MAY RESULTS IN SOME PATCHY VALLEY FOG OVERNIGHT INTO FRIDAY MORNING.
LOW TEMPERATURES TONIGHT WILL RANGE FROM THE LOWER TO MID 50S IN THE
DEEPER VALLEYS OVER SOUTHEAST WEST VIRGINIA AND FAR SOUTHWEST
VIRGINIA TO THE LOWER TO MID 60S IN THE PIEDMONT.
HIGH PRESSURE BUILDS EASTWARD FROM THE CENTRAL PLAINS FRIDAY. THE
HIGH CENTER WILL BRING WITH IT DRIER AIR...PUSHING DEWPOINTS INTO
THE 50S AND LOWER 60S. THE LOWER RELATIVE HUMIDITIES WILL BE A
WELCOME CHANGE FOR MANY. HIGH TEMPERATURES FRIDAY AFTERNOON WILL
BE IN THE MID 70S IN THE NORTHWEST MOUNTAINS TO AROUND 90 DEGREES
IN THE PIEDMONT.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
AS OF 215 PM EDT THURSDAY...
A QUIET AND RATHER COMFORTABLE PERIOD LOOKS IN STORE UNDER BROAD UPPER
TROFFINESS ENHANCED VIA SURFACE HIGH PRESSURE BUILDING OVERHEAD THROUGH
THE WEEKEND. THIS SHOULD RESULT IN MAINLY SUNNY WARM DAYS AND
CLEAR/PLEASANT NIGHTS GIVEN DRIER DEWPOINTS AND SUBSEQUENT LOWER
HUMIDITY THROUGH AT LEAST SUNDAY. ONLY EXCEPTIONS COULD BE WITH MORE
CLOUDS AND POSSIBLY A FEW LIGHT SHOWERS NW UNDER SLIGHTLY BETTER
UPSLOPE LATE SATURDAY...AND THEN PERHAPS OVER THE WESTERN HALF SUNDAY
EVENING WITH A PASSING MID LEVEL SHORTWAVE. HOWEVER GIVEN PROGGED
DRYNESS AND LIKELY ISOLATED NATURE TO ANY SHOWERS OPTING TO LEAVE OUT
ANY POPS OR SHOWER MENTION FOR NOW.
TEMPS LOOK TO REMAIN QUITE PERSISTENT THROUGH THE PERIOD WITH WEAK
DOWNSLOPE/HEATING OF DRY AIR ALLOWING HIGHS TO REMAIN IN THE 85-90
RANGE EAST...AND MOSTLY LOW/MID 80S MOUNTAINS DESPITE THE COOLER/DRIER
AIRMASS. BETTER IMPACT OF THE DRY AIR TO BE FELT DURING THE OVERNIGHTS
WITH LOWS IN THE 50S VALLEYS AND LOW/MID 60S ELSEWHERE. COOLEST NIGHT
AT THIS POINT LOOKS TO BE EARLY SUNDAY WITH THE PASSING OF THE 85H
TROUGH...AND HIGH PRESSURE ABOUT OVERHEAD POSSIBLY ALLOWING A FEW 40S
IN THE DEEPEST NW VALLEYS PENDING ANY RIVER FOG LATE.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 1230 PM EDT THURSDAY...
MEAN 5H TROUGH TO REMAIN ACROSS THE MID ATLANTIC REGION THROUGH MUCH OF
NEXT WEEK WITH STEADY NW FLOW ALOFT BETWEEN UPPER LEVEL LOW PRESSURE
WELL TO THE NORTH AND STRONG RIDGING OVER THE SW STATES. THIS SHOULD
ALLOW FOR AN OVERALL PERSISTENCE TYPE FORECAST THROUGH THE EXTENDED
WITH TOLERANT HUMIDITY LEVELS ALONG WITH LOWS MOSTLY IN THE 60S AND
HIGHS 80S TO LOWER 90S. COVERAGE OF SHOWERS AND STORMS ALSO LIKELY
LIMITED PENDING PROGRESSION OF THE NEXT POSSIBLE COOL SURGE LATE IN THE
PERIOD. HOWEVER WILL ALSO HAVE TO WATCH LINGERING MOISTURE WITH THE
RESIDUAL FRONT NEAR THE COAST WHICH COULD BE LIFTED BACK NORTH BY
APPROACH OF WEAK IMPULSES ALOFT ESPECIALLY EARLY NEXT WEEK. THIS ALONG
WITH HEATING MAY BE ENOUGH TO SPARK ISOLATED CONVECTION MAINLY SOUTH
MONDAY...AND ALONG A PASSING SHORTWAVE TROUGH AXIS CROSSING FROM THE NW
TUESDAY...BUT LOW POPS AT BEST BOTH DAYS.
UPPER TROUGH JUST NORTH OF THE LAKES WILL DEEPEN AGAIN BY MIDWEEK AS
MORE SHORTWAVE ENERGY ROTATES THROUGH AND SLIDES AN ASSOCIATED COLD
FRONT SOUTH TOWARD/INTO THE REGION. HOWEVER MODELS DISAGREE ON THE
AMPLITUDE OF THE DIGGING TROUGH WITH THE GFS MOST AGGRESSIVE WHILE
OTHER SOLUTIONS SLOWER/WEAKER WHILE MAINTAINING MORE CONVECTION ALONG
THE BOUNDARY. FOR NOW WILL GO WITH A WEAKER/SLOWER SCENARIO BUT LEAN
TOWARD THE GFS IN DRIVING THE COOL ADVECTION IN BY THE END OF THE
PERIOD SINCE IT HAS BEEN BEST OF LATE.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
AS OF 140 PM EDT THURSDAY...
A COLD FRONT WILL CONTINUE TO MOVE EAST ACROSS THE REGION THIS
AFTERNOON INTO TONIGHT. MVFR SCT TO BKN CLOUDS WITH POCKETS OF
IFR/LIFR IN CONVECTION THIS AFTERNOON INTO THIS EVENING.
WINDS WILL BECOME NORTHWEST AT 5 TO 12 KTS THIS AFTERNOON...THEN
WEAKEN THIS EVENING INTO TONIGHT.
WITH DRIER AIR WORKING IN THE FOG THREAT SHOULD BE MINIMIZED...THOUGH
THERE IS A SMALL CHANCE THAT LWB/BCB COULD FOG IN GIVEN SOME
SLIGHTLY COOLER AIR OVER MOIST GROUND.
BEHIND THE FRONT...DRIER AIR UNDER VFR CONDITIONS EXPECTED
FRIDAY. NORTHWEST WINDS AT 5 TO 12 KTS EXPECTED FRIDAY AFTERNOON.
HIGH CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE
PERIOD.
EXTENDED AVIATION FORECAST...
UNDER HIGH PRESSURE...DRY AND VFR FRIDAY NIGHT THROUGH SUNDAY.
THE NEXT CHANCE OF MVFR CONDITIONS WILL BE ON MONDAY AND TUESDAY
AS MOISTURE AND A LOW PROBABILITY OF SHOWERS AND THUNDERSTORMS
RETURN TO THE REGION.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...KK/WP
NEAR TERM...KK
SHORT TERM...JH
LONG TERM...JH
AVIATION...KK/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
140 PM EDT THU JUL 30 2015
.SYNOPSIS...
A FRONT WILL SLIDE ACROSS OUR REGION TODAY...STALLING ALONG THE
SOUTHEAST COAST FRIDAY INTO SATURDAY. THIS WILL ALLOW FOR HIGH
PRESSURE TO KEEP MOST OF THE AREA DRY THROUGH THE WEEKEND...AS IT
MOVES IN FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 100 PM EDT THURSDAY...
MADE SOME MINOR ADJUSTMENTS IN CLOUD COVER AND TEMPERATURES
FOR THIS AFTERNOON.
AS OF 919 AM EDT THURSDAY...
ADJUSTED TEMPERATURES WITH LATEST SFC OBS AND GUIDANCE THIS
MORNING INTO THIS AFTERNOON. KFCX WSR-88D SHOWED SCATTERED
CONVECTION MOVING EASTWARD ACROSS SOUTHEAST WEST VIRGINIA
SOUTHWARD INTO THE WESTERN MOUNTAINS. THIS MORNING 12Z/8AM RNK
SOUNDING INDICATED A NORTHWEST FLOW AND PWATS AROUND 1.5 INCHES.
STILL CAN NOT COMPLETELY RULE OUT LOCALLY HEAVY RAINS AND
ISOLATED THREAT FOR WIND GUSTS WITH STRONGER STORMS GIVEN HIGHER
LOW LEVEL LAPSE RATES COMBINED WITH HIGH MOISTURE CONTENT.
LEANED POPS THIS MORNING INTO THIS AFTERNOON TOWARDS HRRR WHICH
CAPTURED CURRENT RADAR IMAGES THE BEST. MORE CHANGES LATER THIS
MORNING.
AS OF 715 AM EDT THURSDAY...
AREA OF SHOWERS/EMBEDDED THUNDERSTORMS MOVING ACROSS SE WV THIS
MORNING INVOF FRONTAL BOUNDARY. THIS FRONT IS GOING TO SLIDE
SOUTHEAST THROUGH THE DAY...WITH MAIN FOCUS WORKING EAST TOWARD
THE PIEDMONT BY EARLY AFTERNOON. NO MAJOR CHANGES TO THE FORECAST
BEYOND UPDATING CHANCES THROUGH 9 AM INTO THE ALLEGHANYS.
PREVIOUS VALID DISCUSSION...
EXPECT FOG TO BE ERODE OR DISSIPATE BY 13Z.
MODELS ARE SIMILAR IN TIMING OF THE FRONT BUT EXPECT TYPICAL
DIFFERENCES ON WHERE BEST THREAT OF SHOWERS/STORMS WILL BE. GIVEN
THERE WILL BE MORE CLOUDS AROUND IN THE WEST THIS MORNING ALONG WITH
FRONT MOVING IN BY LATE MORNING...THINK THE STORM THREAT IS LOWER
OVER THE MTNS. AS WE HEAD INTO THE AFTERNOON...THE EASTERN CWA
SHOULD HAVE ENOUGH SUN TO STEEPEN THE LOW LVL LAPSE RATES. THOUGH
THE DYNAMICS ARE NOT THAT GREAT WITH THE FRONT...CANNOT RULE OUT THE
ISOLATED THREAT FOR A MICROBURST GIVEN HIGHER LOW LVL LAPSE RATES
COMBINED WITH HIGH MOISTURE CONTENT. THE STORM PREDICTION CENTER HAS
THE MARGINAL RISK OVER THE NE PIEDMONT NE OF LYH...AND TO THE SOUTH
OF YADKINVILLE NC. HOWEVER...THINK THE EASTERN CWA WILL HAVE JUST
ENOUGH OF A THREAT TO MENTION IN OUR HAZARDOUS WEATHER OUTLOOK.
HIGHS TODAY WILL DEPEND ON CLOUD COVER...THINKING THE WEST WILL ONLY
GET INTO THE UPPER 70S TO MID 80S...WHILE THE ROANOKE VALLEY EAST TO
THE PIEDMONT HIT UPPER 80S...LOWER 90S. SOME HEAT INDICES COULD
REACH 100 FROM FARMVILLE TO DANVILLE IF MORE SUNSHINE OCCURS GIVEN
DEWPOINTS IN THE LOWER 70S.
TONIGHT...THE MODELS SHOW DRIER AIR OVERSPREADING OUR WESTERN CWA
WHILE THE FRONT EAST SLOWS DOWN AND KEEPS THE HIGHER DEWPOINTS
LINGERING LONGER. THE SHOWER/STORM THREAT WILL BE MOVING OUT OF THE
PIEDMONT BY MIDNIGHT...WITH SKIES CLEARING.
THE DEWPOINTS OVER THE MTNS WILL BE DROPPING INTO THE 50S BY DAWN
FRIDAY...AND YOU WILL BE ABLE TO TELL FRIDAY MORNING THAT THE
HUMIDITY IS LOWER. LOWS WILL RANGE FROM THE MID 50S DEEPER VALLEYS
OVER SE WV/FAR SW VA...TO AROUND 60 ELSEWHERE WEST OF THE BLUE
RIDGE...TO MID 60S FROM ROANOKE EAST TO THE PIEDMONT.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM EDT THURSDAY...
FORECAST MODELS AREA IN VERY GOOD AGREEMENT THAT THE WEATHER PATTERN
FOR THIS WEEKEND WILL BE DOMINATED BY A BROAD UPPER LEVEL TROUGH
EXTENDING SOUTHWARD FROM EASTERN CANADA...WHILE HIGH PRESSURE BUILDS
EASTWARD FROM THE CENTRAL PLAINS IN THE LOW LEVELS. THE HIGH WILL
BRING WITH IT DRIER AIR...PUSHING DEWPOINTS INTO THE 50S AND LOW
60S...WHICH WILL CUT DOWN ON THE HUMIDITY FOR THE WEEKEND.
EXPECT ABUNDANT SUNSHINE FOR FRIDAY WITH VERY LOW RAIN CHANCES IN A
LIGHT NORTH NORTHWESTERLY WINDFLOW.
A REINFORCING COLD FRONT WILL APPROACH FROM THE NORTH ON SATURDAY...
POSSIBLY BRINGING A FEW SHOWERS TO THE WESTERN RIDGES. CONSIDERING
LIMITED MOISTURE IN PLACE AHEAD OF THE APPROACHING FRONT...WILL
MAINTAIN LOW RAIN CHANCES FOR NOW.
WEAK HIGH PRESSURE WILL RETURN FOR SUNDAY...MAKING FOR MOSTLY CLEAR
SKIES...ALTHOUGH CANNOT RULE OUT A FEW POP UP SHOWERS DURING
AFTERNOON/EVENING.
AFTERNOON TEMPERATURES WILL RANGE FROM THE LOW 80S/A FEW UPPER 70S
ACROSS THE MOUNTAINS...TO THE UPPER 80S/LOW 90S ACROSS THE PIEDMONT
EACH DAY. OVERNIGHT LOWS WILL FALL INTO THE UPPER 50S/LOW 60S
WEST...TO THE LOW/MID 60S EAST. WITH COOL AIR DRAINAGE...MAY SEE A
FEW OF THE DEEPER MOUNTAIN VALLEYS FALL TO NEAR 50 DEGREES IN SPOTS.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 1230 PM EDT WEDNESDAY...
PREDOMINATE UPPER TROFFINESS ACROSS THE MID ATLANTIC WILL KEEP NW FLOW
ALOFT IN PLACE FROM THE WEEKEND THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK. THIS SHOULD INITIALLY KEEP OVERALL DRY WEATHER IN PLACE WITH
SURFACE HIGH PRESSURE BUILDING ACROSS THE REGION FROM THE NW SUNDAY-
MONDAY...AND TO THE SOUTH AHEAD OF A REINFORCING COLD FRONT BY
WEDNESDAY. ONLY EXCEPTION TO THIS COULD BE WITH MOISTURE BEING LIFTED
BACK INTO THE SE EARLY NEXT WEEK WITH LOW PRESSURE DEVELOPING ALONG THE
RESIDUAL FRONT NEAR THE COAST. HOWEVER THE EARLIER ECMWF AND CMC ABOUT
THE ONLY SOLUTIONS THAT STILL HINT AT THIS SO BASICALLY LEAVING OUT
MOST POPS OUTSIDE OF SOMETHING ISOLATED SE SECTIONS ON MONDAY.
COLUMN WILL GRADUALLY MOISTEN ENOUGH BY MIDWEEK TO POSSIBLY SUPPORT A
BIT MORE CONVECTION AS WEAK SHORTWAVES ALOFT TRAVERSE THE NW FLOW ON
TUESDAY AHEAD OF A STRONGER UPPER LOW AND COLD FRONT TO THE NORTH
WEDNESDAY. GUIDANCE REMAINS A BIT HESITANT TO PRODUCE MUCH IN THE WAY
OF PRECIP GIVEN MAIN LIFT TO THE NORTH BUT APPEARS ENOUGH FOCUS WITH
HEATING TO SUPPORT SOME LOW POPS TUESDAY AFTERNOON. BETTER CHANCES MAY
COME WEDNESDAY AS THE FRONT SAGS TOWARD THE AREA FROM THE NORTH AND
DEWPOINTS RISE BUT EVEN THEN SUPPORT THIS FAR SOUTH LACKING SO CHANCE
POPS IN ORDER. OTRW MAINLY A PERSISTENCE FORECAST WITH HIGHS 80S TO
AROUND 90 SE AND 60S OVERNIGHT EXCEPT SOME COOLER 50S VALLEYS EARLY IN
THE WEEK AS DEWPOINTS/HUMIDITY REMAIN LOW.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 140 PM EDT THURSDAY...
A COLD FRONT WILL CONTINUE TO MOVE EAST ACROSS THE REGION THIS
AFTERNOON INTO TONIGHT. MVFR SCT TO BKN CLOUDS WITH POCKETS OF
IFR/LIFR IN CONVECTION THIS AFTERNOON INTO THIS EVENING.
WINDS WILL BECOME NORTHWEST AT 5 TO 12 KTS THIS AFTERNOON...THEN
WEAKEN THIS EVENING INTO TONIGHT.
WITH DRIER AIR WORKING IN THE FOG THREAT SHOULD BE MINIMIZED...THOUGH
THERE IS A SMALL CHANCE THAT LWB/BCB COULD FOG IN GIVEN SOME
SLIGHTLY COOLER AIR OVER MOIST GROUND.
BEHIND THE FRONT...DRIER AIR UNDER VFR CONDITIONS EXPECTED
FRIDAY. NORTHWEST WINDS AT 5 TO 12 KTS EXPECTED FRIDAY AFTERNOON.
HIGH CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE
PERIOD.
EXTENDED AVIATION FORECAST...
UNDER HIGH PRESSURE...DRY AND VFR FRIDAY NIGHT THROUGH SUNDAY.
THE NEXT CHANCE OF MVFR CONDITIONS WILL BE ON MONDAY AND TUESDAY
AS MOISTURE AND A LOW PROBABILITY OF SHOWERS AND THUNDERSTORMS
RETURN TO THE REGION.
&&
.EQUIPMENT...
OBSERVATIONS HAVE RETURN FOR LYNCHBURG VIRGINIA AIRPORT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS/WP
NEAR TERM...KK/WP
SHORT TERM...NF
LONG TERM...JH
AVIATION...KK/WP
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
919 AM EDT THU JUL 30 2015
.SYNOPSIS...
A FRONT WILL SLIDE ACROSS OUR REGION TODAY...STALLING ALONG THE
SOUTHEAST COAST FRIDAY INTO SATURDAY. THIS WILL ALLOW FOR HIGH
PRESSURE TO KEEP MOST OF THE AREA DRY THROUGH THE WEEKEND...AS IT
MOVES IN FROM THE WEST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 919 AM EDT THURSDAY...
ADJUSTED TEMPERATURES WITH LATEST SFC OBS AND GUIDANCE THIS
MORNING INTO THIS AFTERNOON. KFCX WSR-88D SHOWED SCATTERED
CONVECTION MOVING EASTWARD ACROSS SOUTHEAST WEST VIRGINIA
SOUTHWARD INTO THE WESTERN MOUNTAINS. THIS MORNING 12Z/8AM RNK
SOUNDING INDICATED A NORTHWEST FLOW AND PWATS AROUND 1.5 INCHES.
STILL CAN NOT COMPLETELY RULE OUT LOCALLY HEAVY RAINS AND
ISOLATED THREAT FOR WIND GUSTS WITH STRONGER STORMS GIVEN HIGHER
LOW LEVEL LAPSE RATES COMBINED WITH HIGH MOISTURE CONTENT.
LEANED POPS THIS MORNING INTO THIS AFTERNOON TOWARDS HRRR WHICH
CAPTURED CURRENT RADAR IMAGES THE BEST. MORE CHANGES LATER THIS
MORNING.
AS OF 715 AM EDT THURSDAY...
AREA OF SHOWERS/EMBEDDED THUNDERSTORMS MOVING ACROSS SE WV THIS
MORNING INVOF FRONTAL BOUNDARY. THIS FRONT IS GOING TO SLIDE
SOUTHEAST THROUGH THE DAY...WITH MAIN FOCUS WORKING EAST TOWARD
THE PIEDMONT BY EARLY AFTERNOON. NO MAJOR CHANGES TO THE FORECAST
BEYOND UPDATING CHANCES THROUGH 9 AM INTO THE ALLEGHANYS.
PREVIOUS VALID DISCUSSION...
EXPECT FOG TO BE ERODE OR DISSIPATE BY 13Z.
MODELS ARE SIMILAR IN TIMING OF THE FRONT BUT EXPECT TYPICAL
DIFFERENCES ON WHERE BEST THREAT OF SHOWERS/STORMS WILL BE. GIVEN
THERE WILL BE MORE CLOUDS AROUND IN THE WEST THIS MORNING ALONG WITH
FRONT MOVING IN BY LATE MORNING...THINK THE STORM THREAT IS LOWER
OVER THE MTNS. AS WE HEAD INTO THE AFTERNOON...THE EASTERN CWA
SHOULD HAVE ENOUGH SUN TO STEEPEN THE LOW LVL LAPSE RATES. THOUGH
THE DYNAMICS ARE NOT THAT GREAT WITH THE FRONT...CANNOT RULE OUT THE
ISOLATED THREAT FOR A MICROBURST GIVEN HIGHER LOW LVL LAPSE RATES
COMBINED WITH HIGH MOISTURE CONTENT. THE STORM PREDICTION CENTER HAS
THE MARGINAL RISK OVER THE NE PIEDMONT NE OF LYH...AND TO THE SOUTH
OF YADKINVILLE NC. HOWEVER...THINK THE EASTERN CWA WILL HAVE JUST
ENOUGH OF A THREAT TO MENTION IN OUR HAZARDOUS WEATHER OUTLOOK.
HIGHS TODAY WILL DEPEND ON CLOUD COVER...THINKING THE WEST WILL ONLY
GET INTO THE UPPER 70S TO MID 80S...WHILE THE ROANOKE VALLEY EAST TO
THE PIEDMONT HIT UPPER 80S...LOWER 90S. SOME HEAT INDICES COULD
REACH 100 FROM FARMVILLE TO DANVILLE IF MORE SUNSHINE OCCURS GIVEN
DEWPOINTS IN THE LOWER 70S.
TONIGHT...THE MODELS SHOW DRIER AIR OVERSPREADING OUR WESTERN CWA
WHILE THE FRONT EAST SLOWS DOWN AND KEEPS THE HIGHER DEWPOINTS
LINGERING LONGER. THE SHOWER/STORM THREAT WILL BE MOVING OUT OF THE
PIEDMONT BY MIDNIGHT...WITH SKIES CLEARING.
THE DEWPOINTS OVER THE MTNS WILL BE DROPPING INTO THE 50S BY DAWN
FRIDAY...AND YOU WILL BE ABLE TO TELL FRIDAY MORNING THAT THE
HUMIDITY IS LOWER. LOWS WILL RANGE FROM THE MID 50S DEEPER VALLEYS
OVER SE WV/FAR SW VA...TO AROUND 60 ELSEWHERE WEST OF THE BLUE
RIDGE...TO MID 60S FROM ROANOKE EAST TO THE PIEDMONT.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM EDT THURSDAY...
FORECAST MODELS AREA IN VERY GOOD AGREEMENT THAT THE WEATHER PATTERN
FOR THIS WEEKEND WILL BE DOMINATED BY A BROAD UPPER LEVEL TROUGH
EXTENDING SOUTHWARD FROM EASTERN CANADA...WHILE HIGH PRESSURE BUILDS
EASTWARD FROM THE CENTRAL PLAINS IN THE LOW LEVELS. THE HIGH WILL
BRING WITH IT DRIER AIR...PUSHING DEWPOINTS INTO THE 50S AND LOW
60S...WHICH WILL CUT DOWN ON THE HUMIDITY FOR THE WEEKEND.
EXPECT ABUNDANT SUNSHINE FOR FRIDAY WITH VERY LOW RAIN CHANCES IN A
LIGHT NORTH NORTHWESTERLY WINDFLOW.
A REINFORCING COLD FRONT WILL APPROACH FROM THE NORTH ON SATURDAY...
POSSIBLY BRINGING A FEW SHOWERS TO THE WESTERN RIDGES. CONSIDERING
LIMITED MOISTURE IN PLACE AHEAD OF THE APPROACHING FRONT...WILL
MAINTAIN LOW RAIN CHANCES FOR NOW.
WEAK HIGH PRESSURE WILL RETURN FOR SUNDAY...MAKING FOR MOSTLY CLEAR
SKIES...ALTHOUGH CANNOT RULE OUT A FEW POP UP SHOWERS DURING
AFTERNOON/EVENING.
AFTERNOON TEMPERATURES WILL RANGE FROM THE LOW 80S/A FEW UPPER 70S
ACROSS THE MOUNTAINS...TO THE UPPER 80S/LOW 90S ACROSS THE PIEDMONT
EACH DAY. OVERNIGHT LOWS WILL FALL INTO THE UPPER 50S/LOW 60S
WEST...TO THE LOW/MID 60S EAST. WITH COOL AIR DRAINAGE...MAY SEE A
FEW OF THE DEEPER MOUNTAIN VALLEYS FALL TO NEAR 50 DEGREES IN SPOTS.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 1230 PM EDT WEDNESDAY...
PREDOMINATE UPPER TROFFINESS ACROSS THE MID ATLANTIC WILL KEEP NW FLOW
ALOFT IN PLACE FROM THE WEEKEND THROUGH AT LEAST THE MIDDLE OF NEXT
WEEK. THIS SHOULD INITIALLY KEEP OVERALL DRY WEATHER IN PLACE WITH
SURFACE HIGH PRESSURE BUILDING ACROSS THE REGION FROM THE NW SUNDAY-
MONDAY...AND TO THE SOUTH AHEAD OF A REINFORCING COLD FRONT BY
WEDNESDAY. ONLY EXCEPTION TO THIS COULD BE WITH MOISTURE BEING LIFTED
BACK INTO THE SE EARLY NEXT WEEK WITH LOW PRESSURE DEVELOPING ALONG THE
RESIDUAL FRONT NEAR THE COAST. HOWEVER THE EARLIER ECMWF AND CMC ABOUT
THE ONLY SOLUTIONS THAT STILL HINT AT THIS SO BASICALLY LEAVING OUT
MOST POPS OUTSIDE OF SOMETHING ISOLATED SE SECTIONS ON MONDAY.
COLUMN WILL GRADUALLY MOISTEN ENOUGH BY MIDWEEK TO POSSIBLY SUPPORT A
BIT MORE CONVECTION AS WEAK SHORTWAVES ALOFT TRAVERSE THE NW FLOW ON
TUESDAY AHEAD OF A STRONGER UPPER LOW AND COLD FRONT TO THE NORTH
WEDNESDAY. GUIDANCE REMAINS A BIT HESITANT TO PRODUCE MUCH IN THE WAY
OF PRECIP GIVEN MAIN LIFT TO THE NORTH BUT APPEARS ENOUGH FOCUS WITH
HEATING TO SUPPORT SOME LOW POPS TUESDAY AFTERNOON. BETTER CHANCES MAY
COME WEDNESDAY AS THE FRONT SAGS TOWARD THE AREA FROM THE NORTH AND
DEWPOINTS RISE BUT EVEN THEN SUPPORT THIS FAR SOUTH LACKING SO CHANCE
POPS IN ORDER. OTRW MAINLY A PERSISTENCE FORECAST WITH HIGHS 80S TO
AROUND 90 SE AND 60S OVERNIGHT EXCEPT SOME COOLER 50S VALLEYS EARLY IN
THE WEEK AS DEWPOINTS/HUMIDITY REMAIN LOW.
&&
.AVIATION /13Z THURSDAY THROUGH MONDAY/...
AS OF 720 AM EDT THURSDAY...
AMD NOT SKED ADDED TO LYH AS NO COMMS INTO OUR COMPUTER SYSTEM.
FAA NOTIFIED.
AS WE HEAD THROUGH THE MORNING GOING TO SEE VFR CONDITIONS FORM AS
FOG/LOW CLOUDS ERODE. SHOWERS WILL IMPACT THE LWB TERMINAL FOR
ANOTHER 1-2 HRS TIL 13-14Z...THEN SHOULD SEE SCATTERED SHOWERS
AND STORMS FURTHER EAST TODAY. KEPT VCTS AT DAN/LYH AND THINK THIS
WILL BE WHERE BETTER COVERAGE...ALBEIT SCATTERED WILL BE GIVEN
MORE SUNSHINE TO AID IN INSTABILITY AHEAD OF THE FRONT.
ONCE THIS FRONT WORKS EAST THE WINDS WILL COME AROUND TO THE
WEST-NORTHWEST AT 5 TO 12 KTS...THEN WEAKEN THIS EVENING.
WITH DRIER AIR WORKING IN THE FOG THREAT SHOULD BE
MINIMIZED...THOUGH THERE IS A SMALL CHANCE THAT LWB/BCB COULD FOG
IN GIVEN SOME SLIGHTLY COOLER AIR OVER MOIST GROUND.
EXTENDED AVIATION FORECAST...
BEHIND THE FRONT THE WEATHER WILL BE DRY AND VFR FRIDAY THROUGH
SUNDAY.
THE NEXT CHANCE OF MVFR CONDITIONS WILL BE ON MONDAY AND TUESDAY
AS MOISTURE AND A LOW PROBABILITY OF SHOWERS AND THUNDERSTORMS
RETURN TO THE REGION.
&&
.EQUIPMENT...
OBSERVATIONS ARE NOT AVAILABLE FROM LYNCHBURG...AND THE FAA HAS
BEEN NOTIFIED OF THIS OUTAGE. NO ESTIMATED TIME OF RESTORATION WAS
GIVEN.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS/WP
NEAR TERM...KK/WP
SHORT TERM...NF
LONG TERM...JH
AVIATION...AMS/KK/WP
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
942 PM CDT FRI JUL 31 2015
.UPDATE...ISOLD BRIEF SHOWERS OR SPRINKLES WILL REMAIN POSSIBLE
OVER SHEBOYGAN COUNTY THROUGH 04Z. THE SHOWERS ARE ASSOCIATED WITH
A SHORTWAVE TROUGH OVER NRN LAKE MI AND A WEAK SFC TROUGH.
FOR LATE TNT AND SAT AM THE HRRR MODEL CONTINUES TO PRODUCE
SHOWERS ACTIVITY WHICH MATCHES UP WITH A MESOSCALE AREA OF WARM
ADVECTION AND MOISTURE FLUX CONVERGENCE THAT WILL TRACK FROM SW MN
INTO FAR SRN WI. WILL KEEP THE CURRENT SLIGHT CHANCE FORECAST FOR
LGT SHOWERS OR SPRINKLES SW OF KMSN AFTER 09Z AND SOUTH OF A LINE
FROM KMSN TO KMKE THROUGH SAT AM. THE WARM...MOIST ADVECTION
PATTERN WILL INCREASE FOR SAT NT INTO SUN WITH SHOWALTER INDICES
REACHING -2C TO -3C. 40-50 POPS MAY HAVE TO BE INCREASED TO LIKELY
FOR THESE PERIODS.
&&
.AVIATION/06Z TAFS/...FEW-SCT070-090 IS EXPECTED FOR SAT WITH
SLIGHT CHANCES OF SHOWERS SAT AM SOUTH OF KMSN AND KMKE DUE TO A
RETURN OF WARM...MOIST ADVECTION. THE WARM...MOIST ADVECTION WILL
INCREASE LATE SAT NT INTO SUN AM WITH HIGHER CHANCES OF SHOWERS
AND TSTORMS EXPECTED.
&&
.PREV DISCUSSION... /ISSUED 343 PM CDT FRI JUL 31 2015/
SHORT TERM...TONIGHT THROUGH MONDAY.
TONIGHT AND SATURDAY - CONFIDENCE...MEDIUM
STRONG NW MID LEVEL FLOW PERSISTS WITH PRIMARY SHORTWAVE OF NOTE
TRAVERSING THROUGH LAKE SUPERIOR INTO LWR MI REGION TONIGHT.
NAM/ARW/NMM/HRRR ALL SHOWING SOME LIGHT PRECIP DEVELOPING LATER IN
THE NIGHT DUE TO LOW LEVEL CONVERGENCE ASSOCIATED WITH SURFACE/850
TROUGH. NOT MUCH SHOWING ON THIS UPSTREAM AND WITH OVERALL DRY AIRMASS
AND POOR TIMING THERMODYNAMICALLY CONFIDENCE NOT GREAT IN MUCH IF
ANYTHING EVOLVING. RAP SOUNDINGS ARE ALL VERY DRY WITH LITTLE IN THE
WAY OF ELEVATED CAPE. HOWEVER NAM/GFS AND HRRR SOUNDINGS SHOW A LITTLE
BETTER MID LEVEL MOISTENING WITH SOME ELEVATED CAPE. CONSENSUS OF MOS
POPS ARE IN THE SINGLE DIGITS. WILL CARRY A A SMALL AREA OF SLGT POPS
FROM LATE TONIGHT INTO EARLY SATURDAY ACROSS PORTIONS OF WRN AND SRN
CWA. FROM LATER IN THE MORNING INTO THE AFTERNOON SURFACE/850 RIDGING
WILL TAKE HOLD WITH A MORE RELAXED PRESSURE GRADIENT IN PLACE TO
SUPPORT A LIGHTER WIND REGIME. 925 TEMPS AVERAGE 22-23C SO EXPECTING
HIGHS BACK INTO THE 80S.
SATURDAY NIGHT...FORECAST CONFIDENCE MEDIUM
WEAK SHORT WAVE APPROACHES SATURDAY NIGHT...CENTERED OVER CWA AT 12Z
SUNDAY...MOVING EAST OF AREA BY 18Z....WITH STRONGER SHORT WAVE
TROUGH MOVING INTO NORTH DAKOTA BY 12Z SUNDAY. LOW-LEVEL THETA-E
ADVECTION MAX CROSSES CWA BETWEEN 03Z AND 06Z SUNDAY...HOWEVER
STRONGER OMEGA TIED WITH STRONGEST FRONTOGENETIC RESPONSE OVER NE WI
TO FOCUSED WARM AIR ADVECTION WITH THE 35-40 KT LOW-LEVEL JET MAX
AHEAD OF STRONG WAVE TO THE NORTHWEST. THIS BETTER FORCING ON THE
NOSE OF THE LLJ SHIFTS EAST AS THE AXIS OF THE LLJ DROPS SOUTH
THROUGH THE STATE OVERNIGHT...BRUSHING THE EASTERN CWA. WILL KEEP
HIGH CHANCE POPS GOING FOR AFTER MIDNIGHT...WITH LATER SHIFTS
POSSIBLY ABLE TO RAISE WITH BETTER CLARITY FROM LATER MODEL RUNS.
SUNDAY...FORECAST CONFIDENCE MEDIUM
PERSISTENT LOW-LEVEL FLOW CONTINUES OVER AREA AHEAD OF SECOND...
STRONGER SHORT WAVE AND ASSOCIATED SURFACE LOW AND COLD FRONT
DIPPING INTO NRN WI BY 00Z MONDAY. PLENTY OF FORCING ALONG/AHEAD OF
850 MB TROUGH AXIS AND SURFACE FRONT BUT STRONG AND DEEP CAPPING
NOTED ON FORECAST SOUNDINGS ESPECIALLY OVER THE WESTERN CWA WITH
PERSISTENT WARM AIR ADVECTION. LESS OF A CAP OVER EASTERN AREAS WITH
HIGHER PW/S. WILL HAVE LOWER CHANCE POPS IN THE MORNING FOR
DEPARTING WARM-AIR ADVECTION FORCING...AND KEEP THEM IN THE
AFTERNOON FOR INSTABILITY AND APPROACHING LOW-LEVEL FORCING WITH THE
LOW.
SUNDAY NIGHT...FORECAST CONFIDENCE MEDIUM
SECOND STRONGER SHORT WAVE DROPS IN SUNDAY NIGHT PUSHING LOW AND
COLD FRONT THROUGH THE SOUTHERN HALF OF THE STATE. BETTER CHANCES
FOR SHOWERS AND STORMS IN THE EVENING BEFORE FRONT DROPS SOUTH IN BY
06Z...WITH CAP ERODING AS MID-LEVELS COOL. KEPT A COLLABORATIVE
SLIGHT CHANCE AFTER 06Z...BUT LOOKS AS IF PCPN WILL BE SOUTH OF AREA
BY 06Z.
MONDAY...FORECAST CONFIDENCE HIGH
DRY WEATHER WITH HIGH PRESSURE BUILDING IN WITH SLIGHTLY COOLER
TEMPERATURES...BUT WITH DEW POINTS FALLING INTO THE 50S WITH DEEP
MIXING.
LONG TERM...MONDAY NIGHT THROUGH FRIDAY...FORECAST CONFIDENCE LOW
MODELS DIFFER WITH LOCATION OF STATIONARY FRONT TO THE SOUTH AND HOW
FAR NORTH PRECIPITATION SHIELD WILL REACH AS WAVE MOVES ALONG
STALLED BOUNDARY TUESDAY AND WEDNESDAY. MOST MODELS KEEP PCPN SOUTH
OF STATE TUESDAY AND SPLIT ON HOW FAR NORTH TO BRING COVERAGE
WEDNESDAY. WITH DRY BROAD HIGH IN PLACE OVER WESTERN GREAT LAKES
WILL GO WITH CONSERVATIVE CONSENSUS SLIGHT CHANCE POPS FOR
WEDNESDAY...WITH CHANCE POPS LIMITED TO THE IL BORDER. MORE
PROGRESSIVE GFS BRINGS A STRONGER LOW ACROSS OR THURSDAY
AFTERNOON/NIGHT WITH ECMWF KEEPING AREA DRY INTO FRIDAY NIGHT.
RESULTING BLEND BRINGS SLIGHT/LOW CHANCES FOR SHOWERS/STORMS FOR THE
END OF THE EXTENDED...THOUGH NOT EVERY PERIOD WILL EVENTUALLY HAVE
PRECIPITATION. AFTER HIGHS IN THE LOW 80S TUESDAY...TEMPERATURES
WILL COOL INTO THE 70S FOR THE REST OF THE EXTENDED...WITH LOWS
MAINLY IN THE 50S.
AVIATION/00Z TAFS/...WNW WINDS EXPECTED TO EASE A BIT THIS EVENING
WITH LOSS OF HEATING. NAM/LATEST HRRR/ARW/NMM WANT TO GENERATE SOME
LIGHT PRECIP INTO SC WI LATE TNGT/ERLY SAT BUT WILL LEAVE MENTION
OUT OF TAF AT THIS TIME. WITH SURFACE/850 RIDGE DRAWING CLOSER ON
SATURDAY EXPECT AN OVERALL LIGHTER WIND REGIME.
MARINE...A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH THE AFTERNOON
DUE TO GUSTY WEST TO NORTHWEST WINDS OF 15 TO 25 KNOTS. A FEW GUSTS
MAY REACH 30 KNOTS AT TIMES. WINDS WILL DIMINISH EARLY THIS
EVENING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...GEHRING
TONIGHT/SATURDAY AND AVIATION/MARINE...COLLAR
SATURDAY NIGHT THROUGH FRIDAY...REM
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SYNOPSIS...
ISSUED AT 227 PM CDT THU JUL 30 2015
SEASONABLY WARM TEMPERATURES EXPECTED THROUGH THE WEEKEND.
THE MAIN BAND OF WESTERLIES IS CURRENTLY ACRS SRN CANADA AND THE
NRN CONUS...HAS LIMITED AMPLITUDE...AND HAS A RIDGE OVER THE W AND
A TROF OVER THE HUDSON BAY RGN. THE MAIN CHG DURING THE FCST
PERIOD WL BE A SLOW AND GRADUAL INCREASE IN AMPLITUDE...WITH THE
UPR TROF EXPANDING SWD. THAT WL TILT THE UPR FLOW INTO THE FCST
AREA MORE NWLY WITH TIME.
TEMPERATURES WILL START OUT WARM...WITH DAYTIME HIGHS THROUGH THE
WEEKEND 4-8F DEG ABV NORMAL. BY EARLY NEXT WK THE UPR FLOW SHOULD
TILT NW ENOUGH TO BRING COOLER AIR FM CANADA INTO THE RGN...LIKELY
DROPPING TEMPS TO A LITTLE BLO NORMAL BY LATE IN THE PERIOD. PCPN
CHCS WILL BE LIMITED SINCE THE VERY HUMID AIR WL REMAIN TO OUR
S...AND THE BEST DYNAMICS WITH THE UPR TROF WL STAY N. ALTHOUGH
ALL IT TAKES AT THIS TIME OF YEAR IS ONE CONVECTIVE EVENT TO
SUPPLY A NORMAL WEEKS WORTH OF PCPN...IT SEEMS LIKELY THAT MOST
AREAS WL END UP RECEIVING BLO NORMAL PCPN FOR THE PERIOD.
&&
.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 227 PM CDT THU JUL 30 2015
MILD TEMPS AND DEWPOINTS IN THE LOWER 50S MADE FOR PLEASANT
CONDITIONS ACROSS NORTHEAST WISCONSIN LATE THIS AFTERNOON.
HOWEVER...19Z WATER VAPOR SHOWED A SHORTWAVE TRACKING THROUGH NE
MINNESOTA AND HEADING FOR NORTHERN WISCONSIN. THIS FEATURE HAS
ALREADY KICKED OFF SCATTERED STORMS THAT WERE MOVING THROUGH NW
WISCONSIN. WITH SOME INSTABILITY IN NORTH CENTRAL WISCONSIN...AND
LAPSE RATES OF 6-7K/KM...THESE STORMS SHOULD MAINTAIN THEMSELVES
THIS AFTERNOON AS THE SHORTWAVE SWINGS THROUGH. NOTHING SEVERE IS
EXPECTED AS CAPES ARE ONLY 500J/KG AT BEST...BUT WITH DRY AIR
ALOFT AND RAP SOUNDINGS SHOWING INVERTED-V-LIKE SIGNATURES...GUSTY
WINDS AND BRIEF HEAVY RAIN IS POSSIBLE THROUGH EARLY THIS EVENING
TO THE NORTH.
ANY LINGERING SHOWERS AND THUNDERSTORMS THIS EVENING SHOULD
QUICKLY DISSIPATE AFTER SUNSET. CLEAR SKIES SHOULD PREVAIL UNTIL
ABOUT MIDNIGHT AS A WEAK FRONT PUSHES THROUGH AND SCATTERED CLOUD
COVER DEVELOPS...WITH BROKEN CLOUDS TO THE NORTHAS BETTER QG
FORCING GIVES SOME ADDED LIFT.WITH VERY LITTLE CHANGE TO THE
OVERALL WEATHER PATTERN...STAYED CLOSE TO LAST NIGHTS LOW
TEMPERATURES WITH A HINT OF THE BEST PERFORMING GUIDANCE THROWN
IN.
FRIDAYS SET UP LOOKS A LOT SIMILAR TO WHAT WE HAD THIS AFTERNOON.
SUNNY AND DRY TO START THE DAY...WITH SOME FAIR WEATHER CU IN THE
AFTERNOON. ANOTHER WEAK SHORTWAVE WILL BE DROPPING THROUGH THE
MEAN FLOW WHICH COULD KICK OFF A FEW SHOWERS TO THE NORTH. WITH NE
WI SITTING ON THE ANTICYCLONIC SIDE OF A BROAD UPPER LEVEL...HAVE
DOUBTS SHOWERS WILL EVEN DEVELOP. FRIDAYS SHORTWAVE WILL NOT BE AS
DEFINED TODAYS WITH LITTLE TO NO ADDED INSTABILITY. HOWEVER
HIGH-RES MODELS CONTINUE TO SHOW ISOLATED PCPN DEVELOPING IN
RESPONSE TO THE LFQ OF A STRONG 300MB JETSTREAK BRUSHING NORTHERN
WISCONSIN. KEPT SLIGHT CHC POPS FRI AFTERNOON...THOUGH CONFINED
PCPN TO ONLY THE FAR NORTH. HIGHS TOMORROW WILL BE A DEGREE OR
TWO COOLER THAN TODAY...WITH CONTINUED BREEZY WEST WINDS THROUGH
NOT AS HIGH AS WE SAW TODAY.
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 227 PM CDT THU JUL 30 2015
DAYTIME TEMPS WL CONT ABV NORMAL FOR A FEW DAYS...THEN EVENTUALLY
COOL AS THE UPR FLOW TILTS NWLY. STAYED CLOSE TO A BLEND OF THE
TOP PERFORMING GUIDANCE PRODUCTS.
HARD TO GET A HANDLE ON SPECIFICS OF THE PCPN FCST GIVEN THE
PATTERN. PCPN CHCS WL BE TIED TO SML SCALE SHRTWVS ROUNDING THE
BASE OF SLOWLY STRENGTHENING LNGWV TROF. CURRENT OP MODEL SUITE
NOT VERY ENCOURAGING FOR THE PCPN WE/VE BEEN CARRYING FOR SAT
NGT...WITH MANY OF THE MODELS NOW TAKING THAT THROUGH TO THE S OF
THE FCST AREA. LATE SUN/SUN NGT LOOK BETTER FOR PCPN AT THIS
POINT. BUT THEN AGAIN IN A PATTERN LIKE THIS...THINGS COULD LOOK
TOTALLY DIFFERENT TOMORROW. STUCK WITH CHC POPS FOR MOST AREAS FOR
SAT NGT...AND AGAIN ON SUN NGT.
NO SIG CHGS MADE TO THE EXTENDED FCST INITIALIZATION GRIDS BASED
ON A BROAD BLEND OF GUIDANCE PRODUCTS.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 1125 AM CDT THU JUL 30 2015
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP THIS AFTERNOON ACROSS NORTHERN WISCONSIN IN RESPONSE TO A
SHORTWAVE SHIFTING THROUGH THE STATE. SOME OF THE PRECIP COULD
AFFECT RHI...HOWEVER COVERAGE SHOULD BE ISOLATED AND NOT ENOUGH
CONFIDENCE TO ADD TO TAF AT THIS TIME. WILL KEEP ON EYE ON HOW
THINGS DEVELOP AND WILL ADD IF COVERAGE IS GREATER AND FARTHER
SOUTH THAN ANTICIPATE CURRENTLY.
OTHERWISE...VFR CONDITIONS WILL CONTINUE ACROSS MUCH OF NE
WISCONSIN WITH GUSTY WEST WINDS. PCPN/CIGS/WINDS WILL DIMINISH
AFTER SUNSET...WITH ONLY A FEW CLOUDS POSSIBLY SWINGING THROUGH
TONIGHT MAINLY TO THE NORTH. FRIDAY SHOULD BE MORE OF THE SAME
WITH VFR CONDITIONS THROUGH MIDDAY. WEST WINDS WILL AGAIN
INCREASE THROUGH THE MORNING...BUT SHOULD NOT BE AS GUSTY AS
TODAY.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....ALLEN
LONG TERM......SKOWRONSKI
AVIATION.......ALLEN
AREA FORECAST DISCUSSION
NWS TUCSON AZ
927 PM MST FRI JUL 31 2015
.SYNOPSIS...ALTHOUGH SOME DRIER AIR WILL MOVE ACROSS THE AREA THIS
WEEKEND INTO NEXT WEEK...THERE WILL BE ENOUGH MOISTURE AROUND FOR A
CHANCE OF SHOWERS AND THUNDERSTORMS...MAINLY ALONG THE INTERNATIONAL
BORDER AS WELL AS THE MOUNTAIN TOPS.
&&
.DISCUSSION...A DISTURBANCE TRACKING NORTHWARD INTO SOUTHERN ARIZONA
CONTINUED TO HELP SUSTAIN THE SHOWER AND THUNDERSTORM ACTIVITY LATE
THIS EVENING. LATEST HRRR SOLUTION INDICATED THAT THIS ACTIVITY WILL
GRADUALLY DIMINISH TONIGHT AS THE DISTURBANCE LIFTS FARTHER NORTH.
RECENT RADAR IMAGERY ALSO INDICATED A DOWNWARD TREND IN THE
INTENSITY AND AREAL COVERAGE. CURRENT FORECAST WAS SHOWING THESE
TRENDS...SO NO UPDATES NECESSARY THIS EVENING. PLEASE REFER TO THE
ADDITIONAL SECTIONS FOR MORE DETAILS.
&&
.AVIATION...VALID THRU 02/06Z.
SCT TO BKN CLOUDS 7-10K FT AGL WITH SCT-NMRS SHRA/TSRA GENERALLY
BEFORE 01/10Z. BRIEF MVFR CONDITIONS WITH ERRATIC WIND GUSTS TO 45
KTS POSSIBLE IN AND AROUND THE STRONGER TSRA. AREAS OF BLDU PSBL W
AND NW OF KTUS AFT 31/22Z. OUTSIDE OF STORM INFLUENCES SFC WINDS
WILL GENERALLY BE LESS THAN 12 KTS WITH A FEW HIGHER GUSTS IN THE
AFTERNOON/EARLY EVENING HOURS. SHRA/TSRA WILL OCCUR AGAIN SATURDAY
AFTERNOON...ALTHOUGH WITH LESS COVERAGE THAN TODAY. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SATURDAY WILL SEE SLIGHTLY LESS SHOWER AND
THUNDERSTORM ACTIVITY. INCREASING SW WINDS ALOFT ON SUNDAY WILL
BRING DRIER AIR INTO THE REGION FOR ISOLATED TO SCATTERED
THUNDERSTORM COVERAGE TO BEGIN NEXT WEEK...WITH A FOCUS MAINLY SOUTH
AND EAST OF TUCSON. OUTSIDE OF THUNDERSTORM WIND GUSTS...20-FT WINDS
WILL GENERALLY BE TERRAIN DRIVEN AND LESS THAN 15 MPH. HOWEVER SOME
AFTERNOON AND EARLY EVENING BREEZINESS IS LIKELY DUE TO DAYTIME
HEATING...ESPECIALLY THROUGH THE GILA VALLEY NEAR SAFFORD.
&&
.PREV DISCUSSION...MODELS INDICATE THAT A WEAK DISTURBANCE COMING UP
FROM THE SOUTH WILL MOVE ACROSS SOUTH CENTRAL ARIZONA THIS EVENING
AND THEN OVER SOUTHWEST ARIZONA EARLY SATURDAY AND WESTERN ARIZONA
MIDDAY SATURDAY. THAT SAID...SATURDAY WE SHOULD SEE LESS
THUNDERSTORM ACTIVITY AS THIS SYSTEM WILL BE OVER SRN NEVADA LATE IN
THE AFTERNOON AND MOISTURE IS EXPECTED TO DECREASE A BIT LATE IN THE
AFTERNOON OR INTO THE EVENING.
BY SUNDAY AND CONTINUING THROUGH AROUND WEDNESDAY THE HIGH IS
EXPECTED TO RECONSOLIDATE IN A WEST TO EAST ORIENTATION ACROSS
NORTHERN MEXICO AND THEN MOVE NORTH OVER THE DESERT SOUTHWEST BY
TUESDAY. AS A RESULT...DRIER SOUTHWEST TO WEST FLOW WILL REDUCE RAIN
CHANCES A BIT AND KEEP THE BEST THREAT FOR SHOWERS AND
THUNDERSTORMS...MAINLY BETWEEN NOGALES AND DOUGLAS AS WELL AS THE
WHITE MOUNTAINS. THIS WILL ALSO RESULT IN WARMER DAYTIME TEMPS
MONDAY THROUGH WEDNESDAY.
FOR LATE WEEK THE HIGH WILL SHIFT TOWARD THE EAST AND RESULT IN A
RETURN FLOW FROM THE SOUTH TO SOUTHEAST AND PULL IN MORE MOISTURE
AND INCREASING THUNDERSTORM CHANCES...BUT STILL JUST ISOLATED TO
SCATTERED IN NATURE.
FOR TUCSON...HIGHS WILL BE NEAR NORMAL SATURDAY...THEN 4 TO 7 DEGS
ABOVE NORMAL EACH DAY THROUGH FRIDAY. HOWEVER...THE WARMEST DAY WILL
LIKELY OCCUR TUESDAY. LOWS WILL RANGE FROM 2 TO 4 DEGS ABOVE NORMAL
EACH MORNING. HOWEVER...THE COOLEST MORNINGS WILL LIKELY OCCUR
MONDAY AND TUESDAY.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
330 AM EDT SAT AUG 1 2015
.SYNOPSIS...
A STALLED FRONTAL BOUNDARY WILL KEEP THE HIGHEST CHANCE OF SHOWERS
AND THUNDERSTORMS ACROSS THE SOUTHEAST MIDLANDS THROUGH THE
WEEKEND. ABOVE NORMAL TEMPERATURES ARE EXPECTED THIS WEEKEND AND
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER RIDGE OUT WEST WITH BROAD TROUGH FROM THE GREAT LAKES TO
THE EAST COAST. SURFACE ANALYSIS AT 07Z INDICATES WEAK FRONTAL
BOUNDARY ACROSS CENTRAL SOUTH CAROLINA. SHARP MOISTURE GRADIENT
ACROSS THE REGION WITH DEEPER MOISTURE TO THE EAST. WEAK FRONT TO
SHIFT TOWARD THE COAST TODAY. APPROACH OF WEAK SHORT WAVE TROUGH
AND WEAK TO MODERATE INSTABILITY SUPPORTS LOW CHANCE POPS IN THE
SOUTHEAST MIDLANDS...MAINLY THIS AFTERNOON. LATEST HRRR SHOWS
SCATTERED COVERAGE IN THAT REGION. RELATIVELY HIGH PRECIPITABLE
WATER REMAINS IN THAT AREA AT LEAST EARLY THIS AFTERNOON AND
SOUNDING ANALYSIS SUGGEST ANY THUNDERSTORMS THAT DEVELOP COULD
PRODUCE HEAVY RAIN ALONG WITH SLOW MOVEMENT. IF DRIER AIR FROM THE
CENTRAL MIDLANDS GETS ENTRAINED INTO STORMS...LOW THREAT STRONG
WINDS ALSO. THREAT IN THE CENTRAL MIDLANDS AND WEST LOW AS
SOUNDINGS APPEAR CAPPED AND DRIER. MET HAS COOL BIAS WITH MAX
TEMPERATURES SO WENT CLOSER TO MAV/ECS GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
THE WEAK FRONTAL BOUNDARY WILL REMAIN ACROSS EASTERN SOUTH
CAROLINA THROUGH THE PERIOD. MODELS APPEARS TO BE DRIER ACROSS
CENTRAL SOUTH CAROLINA AND CSRA AND SOUNDINGS LIKELY CAPPED. SO
LOWERED POPS SLIGHTLY THROUGH THE PERIOD...WIDELY SCATTERED
CONVECTION CONFINED MAINLY IN THE EAST MIDLANDS...LOWER CSRA.
MAX TEMPERATURES MAINLY IN THE MID TO UPPER 90S...LOWS UPPER 60S
TO MID 70S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS HAVE BEEN CONSISTENT SHOWING A RIDGE OVER THE CENTRAL US
WITH A BROAD TROUGH ALONG THE EAST COAST. THE FRONTAL BOUNDARY
WILL REMAIN ALONG THE COAST THROUGH EARLY NEXT WEEK BEFORE
DISSIPATING. THE GFS AND ECMWF ARE IN GOOD AGREEMENT THROUGH
WEDNESDAY...KEEPING THE AREA MAINLY DRY. MOISTURE RETURNS TO THE
REGION TOWARDS THE END OF THE PERIOD FAVORING CLIMATOLOGY FOR
POPS. HIGH TEMPERATURES IN THE MID 90S ARE EXPECTED WITH A GRADUAL
WARMING TREND NEXT WEEK.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
VFR EXPECTED AT CAE/CUB...WITH RESTRICTIONS AT TIMES AT OGB/AGS/DNL
IN POSSIBLE FOG/STRATUS AND/OR CONVECTION.
TIGHT ATMOSPHERIC MOISTURE GRADIENT NOTED CURRENTLY ACROSS THE
REGION...WITH PRECIPITABLE WATER VALUES RANGING FROM 1.3 INCHES NEAR
OUR NORTHERN FORECAST AREA (FA) TO AROUND 2 INCHES NEAR THE
SOUTHERN FA. SURFACE BOUNDARY GENERALLY STRETCHES ACROSS SOUTHERN
PORTIONS OF THE MIDLANDS AND CSRA WHERE IT IS EXPECTED TO REMAIN
NEARLY STATIONARY TODAY. LATEST RADAR IMAGES INDICATE A FEW SHOWERS
HAVE DEVELOPED NEAR OGB AND WILL HANDLE WITH TEMPO GROUPS THERE.
OTHERWISE...FOCUS IN THE NEAR TERM WILL SHIFT TO POSSIBLE FOG AND/OR
STRATUS LATER TONIGHT INTO EARLY SATURDAY MORNING...MAINLY SOUTHERN
TERMINALS. SOME FOG IS EXPECTED...THE EXTENT OF WHICH COULD DEPEND
ON CLOUD COVER...WITH SOME INDICATIONS THAT STRATUS COULD DEVELOP.
LATEST HRRR AND NARRE INDICATE STRATUS OVER SOUTH CENTRAL AND SOUTH
GA SHIFTING TOWARDS THE CSRA AND SOUTHERN MIDLANDS...WHILE OTHER
GUIDANCE INDICATING MIXED RESULTS. LATEST HRRR APPEARS TO BE
EXAGGERATED ON THE NORTHWARD EXTENT OF THE STRATUS IN THE NEAR
TERM...SO WILL GENERALLY LEAN CONSERVATIVE ON STRATUS...EXCEPT AT
OGB WHERE EARLIER RAINFALL COUPLED WITH POSSIBLE ADDITIONAL RAINFALL
IN THE NEAR TERM COULD ACT TO PROMOTE FOG/STRATUS.
AFTER ANY MORNING FOG/STRATUS DISSIPATES...FOCUS WILL SHIFT TO
DIURNAL CONVECTION WHICH IS EXPECTED TO BE FOCUSED ALONG AND SOUTH
OF THE NEARLY STATIONARY BOUNDARY ACROSS OUR SOUTHERN FA. FOR
NOW...WILL INDICATE VCSH AT AGS/DNL...WITH VCTS AT OGB...AFTER 18Z.
DUE TO A MOIST ATMOSPHERE ACROSS THE SOUTHERN FA...ALONG WITH
EXPECTATIONS OF SLOW OR NEARLY STATIONARY STORMS...LOCALLY HEAVY
RAINFALL WILL BE POSSIBLE.
EXTENDED AVIATION OUTLOOK...
RESTRICTIONS POSSIBLE IN LATE NIGHT/EARLY MORNING FOG/STRATUS...WITH
A CHANCE OF DIURNAL THUNDERSTORMS...MAINLY OGB/AGS/DNL...SUNDAY.
LOW POTENTIAL FOR AFTERNOON AND EVENING CONVECTION MONDAY AND
TUESDAY...THOUGH EARLY MORNING FOG WILL BE POSSIBLE AT THE FOG PRONE
SITES AGS AND OGB.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
99
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
149 AM EDT SAT AUG 1 2015
.SYNOPSIS...
A STALLED FRONTAL BOUNDARY WILL KEEP THE HIGHEST CHANCE OF SHOWERS
AND THUNDERSTORMS ACROSS THE SOUTHEAST MIDLANDS THROUGH THE
WEEKEND. ABOVE NORMAL TEMPERATURES ARE EXPECTED THIS WEEKEND AND
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
UPPER RIDGE OUT WEST WITH BROADEN TROUGH FROM THE GREAT LAKES TO
THE EAST COAST. SURFACE OBS SHOWING THAT THE FRONT JUST SOUTH OF
THE CSRA IS SLOWLY TRYING TO LIFT NORTHWARD INTO THE CSRA AND THE
SOUTHEASTERN MIDLANDS. THIS FRONT SHOULD STALL ACROSS THE
MIDLANDS OVERNIGHT.
ISOLATED TO SCATTERED SHOWERS TO CONTINUE ACROSS THE SOUTHERN CSRA
AND EASTERN MIDLANDS ALONG NORTHWARD MOVING OUTFLOWS. DO NOT
ANTICIPATE MUCH CONVECTION FROM THE CENTRAL MIDLANDS NORTHWARD
DUE TO THE DRIER AIR TRYING TO PUSH IN FROM THE NORTH AND THE
PIEDMONT. HAVE FORECAST SLIGHTLY COOLER OVERNIGHT TEMPERATURES IN
THE LOW TO MID 70S...WHICH ARE ARE CONSISTENT WITH MOS GUIDANCE.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
THE WEAK FRONTAL BOUNDARY WILL REMAIN IN THE AREA THROUGH SUNDAY
WITH DRY AIR FEEDING IN FROM THE NORTHWEST. MODELS INDICATE A
SIGNIFICANT CAPPING INVERSION OVER THE CENTRAL AND WESTERN
MIDLANDS MINIMIZING THE THREAT OF CONVECTION IN THE WEST. HOWEVER
CONVERGENCE ALONG THE FRONT COMBINED WITH AMPLE MOISTURE ALONG THE
COAST WILL PROMOTE A CHANCE OF SHOWERS AND THUNDERSTORMS IN THE
EASTERN MIDLANDS AND CSRA. BASED ON MODEL WARMING TRENDS IN
ADDITION TO A RECENT COOL BIAS...HAVE INCREASED HIGHS DURING THE
PERIOD. EXPECT HIGH TEMPERATURES ABOVE CLIMATOLOGY...IN THE MID
90S.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
MODELS HAVE BEEN CONSISTENT SHOWING A RIDGE OVER THE CENTRAL US
WITH A BROAD TROUGH ALONG THE EAST COAST. THE FRONTAL BOUNDARY
WILL REMAIN ALONG THE COAST THROUGH EARLY NEXT WEEK BEFORE
DISSIPATING. THE GFS AND ECMWF ARE IN GOOD AGREEMENT THROUGH
WEDNESDAY...KEEPING THE AREA MAINLY DRY. MOISTURE RETURNS TO THE
REGION TOWARDS THE END OF THE PERIOD FAVORING CLIMATOLOGY FOR
POPS. HIGH TEMPERATURES IN THE MID 90S ARE EXPECTED WITH A GRADUAL
WARMING TREND NEXT WEEK.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
VFR EXPECTED AT CAE/CUB...WITH RESTRICTIONS AT TIMES AT OGB/AGS/DNL
IN POSSIBLE FOG/STRATUS AND/OR CONVECTION.
TIGHT ATMOSPHERIC MOISTURE GRADIENT NOTED CURRENTLY ACROSS THE
REGION...WITH PRECIPITABLE WATER VALUES RANGING FROM 1.3 INCHES NEAR
OUR NORTHERN FORECAST AREA (FA) TO AROUND 2 INCHES NEAR THE
SOUTHERN FA. SURFACE BOUNDARY GENERALLY STRETCHES ACROSS SOUTHERN
PORTIONS OF THE MIDLANDS AND CSRA WHERE IT IS EXPECTED TO REMAIN
NEARLY STATIONARY TODAY. LATEST RADAR IMAGES INDICATE A FEW SHOWERS
HAVE DEVELOPED NEAR OGB AND WILL HANDLE WITH TEMPO GROUPS THERE.
OTHERWISE...FOCUS IN THE NEAR TERM WILL SHIFT TO POSSIBLE FOG AND/OR
STRATUS LATER TONIGHT INTO EARLY SATURDAY MORNING...MAINLY SOUTHERN
TERMINALS. SOME FOG IS EXPECTED...THE EXTENT OF WHICH COULD DEPEND
ON CLOUD COVER...WITH SOME INDICATIONS THAT STRATUS COULD DEVELOP.
LATEST HRRR AND NARRE INDICATE STRATUS OVER SOUTH CENTRAL AND SOUTH
GA SHIFTING TOWARDS THE CSRA AND SOUTHERN MIDLANDS...WHILE OTHER
GUIDANCE INDICATING MIXED RESULTS. LATEST HRRR APPEARS TO BE
EXAGGERATED ON THE NORTHWARD EXTENT OF THE STRATUS IN THE NEAR
TERM...SO WILL GENERALLY LEAN CONSERVATIVE ON STRATUS...EXCEPT AT
OGB WHERE EARLIER RAINFALL COUPLED WITH POSSIBLE ADDITIONAL RAINFALL
IN THE NEAR TERM COULD ACT TO PROMOTE FOG/STRATUS.
AFTER ANY MORNING FOG/STRATUS DISSIPATES...FOCUS WILL SHIFT TO
DIURNAL CONVECTION WHICH IS EXPECTED TO BE FOCUSED ALONG AND SOUTH
OF THE NEARLY STATIONARY BOUNDARY ACROSS OUR SOUTHERN FA. FOR
NOW...WILL INDICATE VCSH AT AGS/DNL...WITH VCTS AT OGB...AFTER 18Z.
DUE TO A MOIST ATMOSPHERE ACROSS THE SOUTHERN FA...ALONG WITH
EXPECTATIONS OF SLOW OR NEARLY STATIONARY STORMS...LOCALLY HEAVY
RAINFALL WILL BE POSSIBLE.
EXTENDED AVIATION OUTLOOK...
RESTRICTIONS POSSIBLE IN LATE NIGHT/EARLY MORNING FOG/STRATUS...WITH
A CHANCE OF DIURNAL THUNDERSTORMS...MAINLY OGB/AGS/DNL...SUNDAY.
LOW POTENTIAL FOR AFTERNOON AND EVENING CONVECTION MONDAY AND
TUESDAY...THOUGH EARLY MORNING FOG WILL BE POSSIBLE AT THE FOG PRONE
SITES AGS AND OGB.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1146 PM CDT FRI JUL 31 2015
.UPDATE...
ISSUED AT 858 PM CDT FRI JUL 31 2015
A FEW ISOLATED THUNDERSTORMS HAVE MANAGED TO FORM ALONG A STALLED
FRONTAL BOUNDARY IN FAR WEST-CENTRAL IL AND COULD REACH INTO
SCHUYLER...CASS...SCOTT...AND MORGAN COUNTIES THIS EVENING. CLOUD
COVER ASSOCIATED WITH STORMS FORMING ALONG THE BOUNDARY TOWARD THE
WEST OVER THE MISSOURI/IOWA BORDER CONTINUE TO SPREAD ACROSS THE
SOUTHERN PORTIONS OF THE CENTRAL IL FORECAST AREA. HAVE UPDATED
FORECASTS FOR THESE TRENDS. OTHERWISE...FORECAST IS ON TRACK FOR A
MOSTLY CLEAR NIGHT ONCE THE CLOUD BAND SLIPS SOUTHWARD...WITH
LOWS REACHING THE LOW TO MID 60S AND LIGHT WEST-NORTHWEST WINDS.
&&
.SHORT TERM...(TONIGHT)
ISSUED AT 315 PM CDT FRI JUL 31 2015
19Z/2PM SURFACE ANALYSIS SHOWS WEAK COLD FRONT SETTLING INTO CENTRAL
ILLINOIS...EXTENDING FROM NEAR RANTOUL TO JUST SOUTH OF QUINCY.
MINIMAL CONVERGENCE ALONG THE FRONT AND AN OVERALL LACK OF DEEP
LAYER MOISTURE HAS LARGELY PREVENTED CONVECTION. THE EXCEPTION HAS
BEEN FURTHER NORTHEAST ACROSS NORTHERN INDIANA WHERE A FEW CLUSTERS
OF THUNDERSTORMS HAVE DEVELOPED. HRRR CONTINUES TO OVER-EMPHASIZE
DEWPOINT POOLING ALONG THE FRONT AND PRODUCES NUMEROUS THUNDERSTORMS
WITH ITS 1 AND 2-HOUR FORECAST. MEANWHILE...THE RAPID REFRESH HAS
CONSISTENTLY PRESENTED A MORE REALISTIC SCENARIO...SUGGESTING ONLY
ISOLATED STORMS MAINLY ACROSS THE E/NE KILX CWA OVER THE NEXT 2-4
HOURS. GIVEN THIS IS THE LOCATION WHERE CU-FIELD IS CURRENTLY MOST
PRONOUNCED...WILL CONTINUE TO FOLLOW THIS SOLUTION CLOSELY. AS A
RESULT...WILL CARRY SLIGHT CHANCE POPS ALONG/NORTHEAST OF A
CHAMPAIGN TO MARSHALL LINE THROUGH THE AFTERNOON. ANY ISOLATED
CONVECTION THAT DEVELOPS WILL QUICKLY DISSIPATE TOWARD
SUNSET...FOLLOWED BY MOSTLY CLEAR AND DRY CONDITIONS TONIGHT.
SLIGHTLY DRIER AIRMASS WILL TRICKLE IN FROM THE NORTHWEST ONCE THE
FRONT PASSES...WITH OVERNIGHT LOW TEMPERATURES DROPPING INTO THE
LOWER TO MIDDLE 60S.
.LONG TERM...(SATURDAY THROUGH FRIDAY)
ISSUED AT 315 PM CDT FRI JUL 31 2015
OVERALL A FAIRLY PERSISTENT WNW FLOW PATTERN WILL REMAIN ACROSS IL
AND MUCH OF THE MIDWEST THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK. QUITE A BIT OF MODEL UNCERTAINTY REGARDING A BREAKDOWN OF THE
WESTERN RIDGE AND DEEPENING OF THE EASTERN TROUGH FOR THE MIDDLE OF
NEXT WEEK.
IN THE NEAR TERM...VERY WARM AND INCREASINGLY HUMID CONDITIONS WILL
BE ON TAP FOR CENTRAL AND EASTERN IL SATURDAY. AN ADVANCING WARM
FRONT AND A CLUSTER OF CONVECTION FROM IOWA/NEBRASKA IS EXPECTED TO
APPROACH AREAS WEST OF THE IL RIVER VALLEY LATE SATURDAY NIGHT AND
INTO SUNDAY MORNING. THE REMNANTS OF THE EARLY MORNING T-STORMS ARE
THEN EXPECTED TO SPREAD ACROSS MOST OF CENTRAL AND EASTERN IL SUNDAY
MORNING AND EARLY AFTERNOON. RESIDUAL BOUNDARIES FROM THIS
CONVECTION SHOULD RESULT IN REDEVELOPMENT OF T-STORMS SUNDAY
AFTERNOON AND INTO THE EVENING...ESPECIALLY ALONG AND NORTH OF I-74.
SOME OF THE STORMS LATER IN THE DAY SUNDAY COULD BE STRONG...MAINLY
DUE TO MODERATE LEVELS OF WIND SHEAR AND INSTABILITY.
MOST OF THE FORECAST AREA WILL BE IN THE WARM SECTOR OF AN ADVANCING
FRONTAL BOUNDARY...YIELDING VERY WARM AND SOMEWHAT HUMID CONDITIONS
MONDAY. THE AFOREMENTIONED FRONT IS EXPECTED TO SLOWLY MOVE INTO
CENTRAL ILLINOIS MONDAY NIGHT AND THEN REMAIN NEARLY STATIONARY FOR
MUCH OF THE WEEK. THIS SHOULD RESULT IN A RATHER UNSETTLED WEATHER
PATTERN WITH THE POTENTIAL FOR SEVERAL PERIODS OF RAIN FROM LATE
MONDAY...ON AND OFF...THROUGH THE END OF THE WEEK.
THE UNCERTAINTY IN THE MODELS REVOLVES AROUND THE DETAILS OF
POSSIBLE SHORTWAVE ENERGY BREAKING THROUGH THE WESTERN U.S. RIDGE
AND INTERACTING WITH THE FRONT. THE GFS IS A BIT MORE AGGRESSIVE WITH
THIS THAN THE EUROPEAN MODEL. HOWEVER...THE EUROPEAN NOT ONLY
UNDERPLAYS THE AFFECTS OF THIS BUT KEEPS THE SURFACE FRONT FARTHER
NORTH. UNTIL THE DETAILS ARE WORKED OUT IT IS HARD TO PIN DOWN
WHERE A THREAT OF PERSISTENT...POSSIBLY HEAVY RAIN MAY SET UP THE
MIDDLE OF NEXT WEEK. THUS...WILL NOT MAKE TOO MANY MAJOR CHANGES
TO THE FORECAST AND KEEP CHANCE POPS FOR THUNDERSTORMS ACROSS A
LARGE PART OF THE FORECAST AREA.
THE ONE THING THE MODELS DO AGREE ON IS THAT WITH THE PERIODS OF
CONVECTION AND RESIDUAL CLOUD COVER...TEMPERATURES SHOULD BE BELOW
SEASONAL NORMALS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1146 PM CDT FRI JUL 31 2015
VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24 HOURS AS HIGH
PRESSURE CONTINUES OVER THE AREA WITH A FRONTAL BOUNDARY STALLED
OUT SOUTH OF THE CENTRAL IL TERMINALS. ISOLATED SHOWERS ALONG THE
BOUNDARY WILL CONTINUE EARLY IN THE OVERNIGHT HOURS...BUT THESE
ARE EXPECTED TO REMAIN SOUTH OF THE CENTRAL IL TERMINALS AND ONLY
EXPECTING SCATTERED SCATTERED CLOUD COVER AT KSPI AND PERHAPS
KDEC. WINDS NW 3-5 KTS OVERNIGHT...BECOMING SW 8-12 KTS AFTER 15Z
SATURDAY. SW WINDS DECREASING AFTER 00Z.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...ONTON
SHORT TERM...BARNES
LONG TERM...MILLER
AVIATION...ONTON
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1125 PM MDT FRI JUL 31 2015
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 141 PM MDT FRI JUL 31 2015
PERSISTENT UPPER LEVEL RIDGE CONTINUES TO DOMINATE PATTERN ACROSS
WESTERN US THROUGH THE SOUTHERN PLAINS...WITH NW FLOW ACROSS THE
NORTHERN PLAINS. WV IMAGERY SHOWS MONSOONAL MOISTURE PLUME EXTENDING
FROM THE BAJA PENINSULA ACROSS THE FOUR CORNER AND INTO THE HIGH
PLAINS WITH SEVERAL WEAK SHORTWAVE TROUGHS ROTATING AROUND RIDGE
INTO THE SOUTHERN PLAINS AND THROUGH THE NW FLOW ALONG THE MISSOURI
RIVER VALLEY. AT THE SURFACE...MEAN SURFACE TROUGH EXTENDS ACROSS
NORTHERN COLORADO INTO CENTRAL NEBRASKA...WITH WEAK FLOW AND A
SECONDARY WEAK TROUGH AXIS/SURFACE CONVERGENT ZONE ALONG THE KS CO
BORDER EXTENDING SOUTH INTO SOUTH CENTRAL KS.
MODELS CONTINUE TO UNDERESTIMATE TDS WITH 60-70F TD VALUES REPORTED
MOST OF THE DAY...FINALLY BEGINNING TO FALL IN OUR NW. RESULT IS
MUCH HIGHER CAPE VALUES THAN PREVIOUSLY ADVERTISED WITH RAP ANALYSIS
SHOWS A SHARP GRADIENT OF SB CAPE FROM 250 J/KG IN NORTHEAST
COLORADO TO 3000 J/KG OVER OUR SOUTHERN CWA. CONSIDERING THE MOIST
BL LAYER AND FAVORABLE CAPE PROFILES OVER MOST OF THE AREA IT WON`T
TAKE MUCH FOR THUNDERSTORMS TO DEVELOP. WITH ONLY WEAK HEIGHT FALLS
THIS AFTERNOON/TONIGHT AND MODELS SHOWING ALMOST NO ACTIVITY
INITIATING OVER OUR CA (DESPITE LOW CINH)...I AM FAVORING ISOLATED
THUNDERSTORM MENTION FOR NOW. AS WITH LAST NIGHT...VERY LITTLE STORM
MOTION (0-6KM 0-5KT ACROSS MUCH OF THE AREA) WILL RESULT IN
POTENTIAL FOR FLASH FLOODING. IF CELL MERGERS OCCUR AND ARE ABLE TO
DEVELOP A COLD POOL OR OUTFLOW WE COULD SEE BETTER COVERAGE. LOW
CONFIDENCE AT THIS POINT.
SATURDAY...PATTERN WILL BE VERY SIMILAR AS TODAY WITH SEASONAL HIGHS
(UPPER 80S-MID 90S). GUIDANCE ACTUALLY INDICATING SUBSIDENCE WILL BE
IN PLACE...SO WHILE HIGH CAPE VALUES/DECENT MOISTURE PROFILES WILL
LIKELY SET UP OVER THE CWA ONCE AGAIN CONFIDENCE IN ANY INITIATION
IS EVEN LOWER THAN TODAY. I DECIDED TO KEEP THUNDERSTORM MENTION
OUT FOR NOW.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 200 PM MDT FRI JUL 31 2015
FOR THE EXTENDED PERIOD...THE LATTER PORTION OF THE WEEKEND RIGHT
THROUGH MUCH OF NEXT WEEK...THE ENTIRE TRI STATE REGION WILL SEE
ABOVE NORMAL TEMPERATURES BROUGHT ABOUT BY A STRONG AMPLIFIED
500/700 MB RIDGE OVER THE WESTERN PORTION OF THE COUNTRY...THAT
SHIFTS EASTWARD INTO THE PLAINS REGION BY NEXT WEDNESDAY. LATEST
MODEL RUNS STILL SHOW 850 MB TEMPS RANGING FROM +29C TO ALMOST
+35C...UNDER WNW UPPER FLOW. THIS IS GOING TO GIVE THE AREA DAYTIME
HIGHS WELL INTO THE 90S...WARMEST ON WEDNESDAY WHEN UPPER RIDGE AXIS
SETTLES OVER THE REGION AND COULD GIVE MID TO UPPER 90S TO THE AREA.
COOLER AIR COULD ARRIVE DURING THE DAY FRIDAY WITH SURFACE RIDGE
BUILDING SOUTH THRU THE PLAINS AFTER FRONTAL PASSAGE LATE THURSDAY
NIGHT.
DESPITE STRONG RIDGING OVER THE REGION OVER THE NEXT WEEK...SEVERAL
SHORTWAVES ARE EXPECTED TO TRAVERSE OVER THE NORTHERN HALF OF THE
RIDGE...BRINGING THE CHANCE FOR SHOWERS/THUNDERSTORMS. THIS ACTIVITY
THOUGH WILL SPARE THE FORECAST AREA FOR THIS UPCOMING WEEKEND...ONLY
TO BEGIN WITH A STRONG TROUGH LATE MONDAY INTO TUESDAY AND THEN
SUBSEQUENT SYSTEMS. BEST CHANCES FOR PRECIP THOUGH AS WEEK
PROGRESSES WILL BEGIN TO SHIFT MORE EASTWARD OVER THE CWA...DUE TO
MOVEMENT OF UPPER RIDGE WHICH WILL AFFECT PLACEMENT OF EACH LATTER
SHORTWAVE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1121 PM MDT FRI JUL 31 2015
VFR CONDITIONS ARE EXPECTED FOR BOTH TERMINALS FOR THE DURATION OF
THE TAF PERIOD. GUSTY WINDS WILL PICK UP TOMORROW AFTERNOON AS A
SURFACE TROUGH STRENGTHENS...BUT WINDS WILL REDUCE TOWARDS THE
EVENING HOURS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JN
AVIATION...MK
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1128 PM CDT FRI JUL 31 2015
...UPDATED FOR AVIATION...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 1226 PM CDT FRI JUL 31 2015
THE SUMMER SUBTROPICAL RIDGE WAS CENTERED OVER ITS CLIMATOLOGICAL
POSITION FROM THE SOUTHERN ROCKIES INTO TEXAS TODAY. IN THE UPPER
TROPOSPHERE, WEST NORTHWEST FLOW EXTENDED FROM THE NORTHERN ROCKIES
THROUGH THE UPPER MISSISSIPPI VALLEY. WESTERN KANSAS WAS ON THE
SOUTH EDGE OF THE WESTERLIES AT 250MB. THE MESOSCALE CONVECTIVE
SYSTEM (MCS) THAT AFFECTED EXTREME SOUTHWEST KANSAS OVERNIGHT AND
THIS MORNING WAS DECREASING IN AREAL EXTENT AND MOVING VERY SLOWLY
TO THE EAST-SOUTHEAST...FOLLOWING ROUGHLY THE 3-8KM AGL MEAN FLOW
VECTOR (JUST NORTH OF THE CENTER OF THE MEAN ANTICYCLONE IN THIS
LAYER OVER WEST TEXAS). A COUPLE OF MESOSCALE CONVECTIVE VORTICITY
MAXIMAS COULD BE IDENTIFIED THROUGH VISIBLE SATELLITE AND EVEN THE
HOURLY RAP ANALYSIS FROM NEAR TUCUMCARI NEW MEXICO TO NEAR
SPRINGFIELD COLORADO. IT WOULD APPEAR AS OF THESE MESOSCALE FEATURES
WERE ACTUALLY HELPING TO MAINTAIN THE SMALL MCS THROUGH THE EARLY
AFTERNOON HOURS AS THE LEADING EDGE OF IT WAS MOVING INTO THE FAR
EASTERN OK-TX PANHANDLES. THE VERY NORTHERN EXTENT OF THIS MCS
EXTENDED INTO MORTON AND SEWARD COUNTIES, WHICH WAS HAVING AN IMPACT
ON SURFACE TEMPERATURES (COOLER THAN FORECAST IN THIS AREA). WE HAVE
ADJUSTED THE DAYTIME TEMPERATURES DOWNWARD ACROSS FAR SOUTHWEST
KANSAS AS A RESULT. ELSEWHERE...ESPECIALLY ACROSS WEST CENTRAL AND
CENTRAL KANSAS NORTH OF HIGHWAY 96, TEMPERATURES SHOULD TOP OUT IN
THE LOWER TO MID 90S.
AS WE GO IN TO TONIGHT...ANOTHER SMALL MCS SHOULD EVOLVE THROUGH THE
LATE NIGHT HOURS FROM CONVECTION ACROSS THE HIGHER TERRAIN OF THE
RATON MESA REGION. THIS CONVECTION SHOULD FOLLOW THE SAME GENERAL
TRACK AS THIS MORNINGS MCS, SO WE WILL KEEP THE BEST POPS ACROSS FAR
SOUTHWEST KANSAS AGAIN IN THE 40-50 PERCENT RANGE. THE BULK OF LATE
TONIGHT/TOMORROWS MCS SHOULD REMAIN ACROSS THE PANHANDLES REGION. IT
SHOULD BE CLOSE TO A RINSE AND REPEAT TYPE OF DEAL TOMORROW WITH A
SLOWLY DECAYING MCS SOMEWHERE JUST SOUTH OF OUR FORECAST AREA (OR
PERHAPS CLIPPING MORTON-SEWARD-MEADE) WITH WARMEST TEMPERATURES UP
NORTH ALONG I-70 (MID 90S) AND COOLEST TEMPERATURES ALONG THE OK
BORDER (LOWER-MID 80S, IF EVEN THAT WARM).
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 338 PM CDT FRI JUL 31 2015
THE BEST CHANCE FOR THE NEXT ORGANIZED PRECIPITATION EVENT WILL BE
MONDAY NIGHT INTO TUESDAY. THE GLOBAL SPECTRAL MODELS CONTINUE TO
SHOW AN INTERACTION BETWEEN MONSOON PERTURBATIONS MOVING NORTHWARD
THROUGH THE DESERT SOUTHWEST...AND AN INCOMING SUBTROPICAL PACIFIC
JET MOVING INTO THE INTERMOUNTAIN WEST REGION. THIS WILL ACT TO
SHIFT THE MONSOON CIRCULATION NORTHEASTWARD SOME...ENHANCING THE
PRECIPITATION POTENTIAL FOR SOUTHWEST KANSAS. IT VERY WELL COULD BE
JUST ONE BIG MCS WE SEE OUT OF THIS EVENT, IN WHICH CASE IF THE
ECMWF HAS A HANDLE ON THINGS, WOULD BE MONDAY NIGHT. THIS IS WHEN
THE HIGHEST POPS ARE IN THE GRIDS FOR THE ENTIRE REGION. ONCE THAT
WAVE EXITS THE CENTRAL PLAINS...THE SUMMER SUBTROPICAL RIDGE WILL
BUILD BACK IN, HOWEVER DEEP TROPOSPHERIC MONSOON MOISTURE WILL BE
FAIRLY SCANT AND IT WILL NEED TO BE RECHARGED AGAIN BY WAY OF LATE
DAY HIGH TERRAIN THUNDERSTORMS. THE LATEST ECMWF FAVORS RIDGE-
BUILDING INTO THE NORTHERN PLAINS WHICH WOULD RESULT IN A WARMING OF
THE LOWER TROPOSPHERE AND SURFACE TEMPERATURES REACHING OR EXCEEDING
THE UPPER 90S BY MID TO LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1121 PM CDT FRI JUL 31 2015
VFR CONDITIONS ARE EXPECTED INTO TODAY. AS SURFACE HIGH PRESSURE
MOVES SOUTH AND A LEE TROUGH DEVELOPS TODAY, LIGHT SOUTHERLY WINDS
WILL INCREASE BY AFTERNOON TO 12-20KT, THEN RELAX AGAIN AFTER
02Z. THERE COULD BE SOME LIGHT GROUND FOG AND HAZE NEAR KDDC AND
KGCK FROM 11-14Z THIS MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 68 87 67 93 / 10 10 10 10
GCK 67 87 67 92 / 10 10 10 10
EHA 66 85 67 92 / 30 30 20 10
LBL 68 83 68 92 / 30 30 20 10
HYS 67 93 67 95 / 10 10 10 10
P28 71 90 70 94 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...UMSCHEID
AVIATION...KRUSE
AREA FORECAST DISCUSSION
NWS JACKSON KY
358 AM EDT SAT AUG 1 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 305 AM EDT SAT AUG 1 2015
06Z SFC ANALYSIS SHOWS THAT HIGH PRESSURE REMAINS IN CONTROL OF
EAST KENTUCKY/S WEATHER THIS EARLY MORNING. THIS HIGH HAS KEPT
CLOUD COVER TO A MINIMUM AND IS SUPPORTING A DECENT RIDGE TO
VALLEY TEMPERATURE SPLIT ON THE ORDER OF 5 TO 10 DEGREES. AT THE
SAME TIME DEWPOINTS ARE RUNNING IN THE LOWER 60S. AS TEMPERATURES
CONTINUE TO RADIATE LOWER FOR THE REST OF THE NIGHT THE DEWPOINTS
WILL ALSO CREEP DOWN...BUT IN THE DEEPER VALLEYS PROBABLY NOT FAST
ENOUGH TO PREVENT THE DEVELOPMENT OF FOG...ESPECIALLY NEAR RIVERS
AND BODIES OF WATER. WINDS WILL BE LIGHT THROUGH DAWN PERHAPS
CONTRIBUTING TO THE LOCALLY DENSE FOG IN THE MORE SHELTERED RIVER
VALLEY SPOTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE LONGWAVE PATTERN
AS THEY ALL DEPICT A SLOWLY DEEPENING...LARGE TROUGH THROUGH THE
NORTHEAST PORTION OF THE CONTINENT STRETCHING SOUTH THROUGH THE
OHIO VALLEY OVER THE WEEKEND. THE NORTHWEST FLOW ASSOCIATED WITH
THIS WILL BRING MINOR SHORTWAVES OVER KENTUCKY DURING THE PERIOD
BUT NOT MUCH IN THE WAY OF MESOSCALE AMPLIFICATION UNTIL PERHAPS
SUNDAY AFTERNOON WHEN A HEALTHIER ONE PASSES BY TO THE NORTH. THE
NAM CONTINUES TO BE ON THE STRONGER SIDE OF THE MODEL SPECTRUM
WITH THE LARGER TROUGH AND THIS WAVE LATE IN THE PERIOD.
ACCORDINGLY...HAVE GONE WITH MORE OF A MODEL BLEND FAVORING A MIX
OF THE ECMWF AND GFS OUTSIDE OF THE NEAR TERM WHERE THE HRRR AND
NAM12 ARE REASONABLE.
SENSIBLE WEATHER WILL FEATURE A VERY PLEASANT MID SUMMER WEEKEND
AS THE AFTERNOON WARMTH IS KEPT COMFORTABLE BY RELATIVELY LOW
HUMIDITIES WROUGHT BY A MIDDAY AND AFTERNOON MIX DOWN OF DRIER
AIR FROM THE MID LEVELS. THIS WILL KEEP CLOUD COVER TO A MINIMUM
THROUGH THE PERIOD AND ALSO LEAD TO ANOTHER NIGHT OF GOOD
RADIATIONAL COOLING FOR SUNDAY MORNING. SIMILARLY...PATCHY FOG
WILL LIKELY BE LIMITED TO THE DEEPER RIVER VALLEY LOCATIONS BOTH
THIS MORNING AND SUNDAY MORNING...THOUGH LOCALLY DENSE POCKETS
WILL BE POSSIBLE AS WELL.
AGAIN USED THE SHORTBLEND MODEL AS A STARTING POINT FOR THE
T/TD/WIND GRIDS THROUGH THE DAY FOLLOWED BY THE SUPERBLEND INTO
SUNDAY. DID MAKE SOME SIGNIFICANT ADJUSTMENTS TO TEMPERATURES
THIS MORNING AND TONIGHT WITH RESPECT TO RIDGE AND VALLEY
DIFFERENCES ONCE...AND AS...THE INVERSION IS IN PLACE. AS FOR
POPS...KEPT THEM LOW AND IN LINE WITH THE DRIER MET GUIDANCE.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 358 AM EDT SAT AUG 1 2015
THE EXTENDED PERIOD BEGINS WITH THE UPPER LEVEL PATTERN FEATURING A
RIDGE OVER THE WESTERN CONUS AND A TROUGH OVER THE EAST AND A
CLOSED LOW CENTERED JUST SOUTH OF THE HUDSON BAY AREA. THIS
PATTERN...THOUGH WITH SOME SHIFTING OF FEATURES EACH
DAY...REMAINS IN PLACE FOR JUST ABOUT THE ENTIRE EXTENDED. TO
START THE EXTENDED...A WEAK SHORTWAVE WILL PASS THROUGH THE LOWER
GREAT LAKES REGION BRINGING A SURFACE COLD FRONT ACROSS NORTHERN
KENTUCKY AND THE CHANCE FOR SOME AFTERNOON SHOWERS AND
THUNDERSTORMS. BY TUESDAY...A SURFACE STATIONARY BOUNDARY SETS UP
ACROSS SOUTHERN OH...IN...AND IL ALLOWING FOR A FOCUS OF SHOWER
AND THUNDERSTORM DEVELOPMENT ALONG NORTHERN KENTUCKY ON MONDAY AND
TUESDAY.
THROUGH THE REST OF THE EXTENDED...THE PATTERN IN PLACE WILL BE
FAVORABLE FOR MCS/S IN THIS NORTHWEST FLOW. THIS HOLDS TRUE
THROUGH TUESDAY AND THURSDAY PERIOD. HAVE KEPT THE SUGGESTED POPS
INHERITED BY THE SUPER BLEND WITH INSTABILITY AND MOISTURE IN
PLACE...THIS SEEMS LIKELY ACROSS EASTERN KENTUCKY...ESPECIALLY
WITH THE INCONSISTENCY IN THE GFS AND EURO. BY THE WEDNESDAY
EVENING AND WEDNESDAY NIGHT PERIOD...A BETTER COMPLEX IS SEEMS
POISED TO MOVE INTO THE AREA. HOWEVER...AS STATED EARLIER...THE GFS
AND EURO HAVE BEEN INCONSISTENT WITH THE TRACK AND TIMING THIS
LATE IN THE EXTENDED AS RECENT RUNS HAVE THE UPPER TROUGH PUSHING
FURTHER SOUTH AS WELL AS THE SURFACE GRADIENT. OVERALL...THE DAY
5...6 AND 7 PERIOD SEEMS QUITE ACTIVE AND WILL KEEP THE HIGH
CHANCE POPS ADVERTISED BY THE SUPER BLEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 230 AM EDT SAT AUG 1 2015
HIGH PRESSURE WILL KEEP VFR CONDITIONS IN THE TAF FORECAST FOR
MOST OF THE SITES THROUGH THE PERIOD. THE EXCEPTION MAY BE AT SME
LATE THIS NIGHT AS THEIR DEWPOINT DEPRESSION IS CURRENTLY THE
SMALLEST. ACCORDINGLY...HAVE ADDED A PERIOD OF MVFR FOG TO THAT
SITE WHILE LEAVING THE REST CLEAN. OUTSIDE OF THE FORMAL TAF
SITES...PATCHY FOG WILL BE FOUND IN THE LOWER ELEVATIONS TOWARDS
DAWN...BECOMING LOCALLY DENSE FOR A BRIEF TIME. ANY FOG WILL
CLEAR OUT BY MID MORNING WITH VFR CONDITIONS CONTINUING INTO
SATURDAY NIGHT AT THE AIRPORTS. WINDS THROUGH THE PERIOD WILL BE
LIGHT AND VARIABLE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
305 AM EDT SAT AUG 1 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 305 AM EDT SAT AUG 1 2015
06Z SFC ANALYSIS SHOWS THAT HIGH PRESSURE REMAINS IN CONTROL OF
EAST KENTUCKY/S WEATHER THIS EARLY MORNING. THIS HIGH HAS KEPT
CLOUD COVER TO A MINIMUM AND IS SUPPORTING A DECENT RIDGE TO
VALLEY TEMPERATURE SPLIT ON THE ORDER OF 5 TO 10 DEGREES. AT THE
SAME TIME DEWPOINTS ARE RUNNING IN THE LOWER 60S. AS TEMPERATURES
CONTINUE TO RADIATE LOWER FOR THE REST OF THE NIGHT THE DEWPOINTS
WILL ALSO CREEP DOWN...BUT IN THE DEEPER VALLEYS PROBABLY NOT FAST
ENOUGH TO PREVENT THE DEVELOPMENT OF FOG...ESPECIALLY NEAR RIVERS
AND BODIES OF WATER. WINDS WILL BE LIGHT THROUGH DAWN PERHAPS
CONTRIBUTING TO THE LOCALLY DENSE FOG IN THE MORE SHELTERED RIVER
VALLEY SPOTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE LONGWAVE PATTERN
AS THEY ALL DEPICT A SLOWLY DEEPENING...LARGE TROUGH THROUGH THE
NORTHEAST PORTION OF THE CONTINENT STRETCHING SOUTH THROUGH THE
OHIO VALLEY OVER THE WEEKEND. THE NORTHWEST FLOW ASSOCIATED WITH
THIS WILL BRING MINOR SHORTWAVES OVER KENTUCKY DURING THE PERIOD
BUT NOT MUCH IN THE WAY OF MESOSCALE AMPLIFICATION UNTIL PERHAPS
SUNDAY AFTERNOON WHEN A HEALTHIER ONE PASSES BY TO THE NORTH. THE
NAM CONTINUES TO BE ON THE STRONGER SIDE OF THE MODEL SPECTRUM
WITH THE LARGER TROUGH AND THIS WAVE LATE IN THE PERIOD.
ACCORDINGLY...HAVE GONE WITH MORE OF A MODEL BLEND FAVORING A MIX
OF THE ECMWF AND GFS OUTSIDE OF THE NEAR TERM WHERE THE HRRR AND
NAM12 ARE REASONABLE.
SENSIBLE WEATHER WILL FEATURE A VERY PLEASANT MID SUMMER WEEKEND
AS THE AFTERNOON WARMTH IS KEPT COMFORTABLE BY RELATIVELY LOW
HUMIDITIES WROUGHT BY A MIDDAY AND AFTERNOON MIX DOWN OF DRIER
AIR FROM THE MID LEVELS. THIS WILL KEEP CLOUD COVER TO A MINIMUM
THROUGH THE PERIOD AND ALSO LEAD TO ANOTHER NIGHT OF GOOD
RADIATIONAL COOLING FOR SUNDAY MORNING. SIMILARLY...PATCHY FOG
WILL LIKELY BE LIMITED TO THE DEEPER RIVER VALLEY LOCATIONS BOTH
THIS MORNING AND SUNDAY MORNING...THOUGH LOCALLY DENSE POCKETS
WILL BE POSSIBLE AS WELL.
AGAIN USED THE SHORTBLEND MODEL AS A STARTING POINT FOR THE
T/TD/WIND GRIDS THROUGH THE DAY FOLLOWED BY THE SUPERBLEND INTO
SUNDAY. DID MAKE SOME SIGNIFICANT ADJUSTMENTS TO TEMPERATURES
THIS MORNING AND TONIGHT WITH RESPECT TO RIDGE AND VALLEY
DIFFERENCES ONCE...AND AS...THE INVERSION IS IN PLACE. AS FOR
POPS...KEPT THEM LOW AND IN LINE WITH THE DRIER MET GUIDANCE.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 344 PM EDT FRI JUL 31 2015
THE PERIOD IS EXPECTED TO BEGIN WITH A RIDGE EXTENDING FROM THE
SOUTHERN PLAINS INTO THE CENTRAL ROCKIES AND A TROUGH TROUGH OVER
MUCH OF THE EASTERN CONUS EXTENDING SOUTH FROM A CLOSED LOW OVER
THE SOUTHERN HUDSON BAY REGION. AT THAT POINT...A FEW SHORTWAVES
WILL BE MOVING INTO THE TROUGH ACROSS THE GREAT LAKES REGION. A
FEW SHORTWAVES WILL ALSO BE WORKING AROUND THE RIDGE ACROSS THE
WESTERN CONUS TO START THE PERIOD...WITH ANOTHER FURTHER NORTH
MOVING INTO SOUTHWESTERN CANADA. AT THE SFC...HIGH PRESSURE IS
EXPECTED TO BE CENTERED OVER THE CENTRAL APPALACHIANS AT THAT
POINT...WITH SFC LOW PRESSURE ALSO CENTERED OVER THE SOUTHERN
HUDSON BAY REGION AND A COLD FRONT EXTENDING SOUTH INTO THE
NORTHERN GREAT LAKES AND NORTHERN PLAINS...BEFORE BECOMING
STATIONARY AND EXTENDING NORTHWEST INTO THE NORTHERN ROCKIES.
THE CLOSED LOW INITIALLY NEAR SOUTHERN HUDSON BAY SHOULD MEANDER
SOUTH AND SOUTHEAST INTO ONTARIO AND QUEBEC AND OPEN UP A BIT
THROUGH THE EARLY TO MIDDLE PART OF NEXT WEEK. A SHORTWAVE OR TWO
ROTATING AROUND THIS LOW SHOULD WORK INTO THE NORTHERN GREAT LAKES
TO END THE WEEKEND AND ROTATE THROUGH THE GREAT LAKES AND INTO
THE NORTHEASTERN STATES THROUGH TUESDAY. THEN A SHORTWAVE WORKING
AROUND THE RIDGE SHOULD APPROACH THE MS RIVER VALLEY. THE MODELS
ARE NOT IN AGREEMENT WITH THE EVOLUTION AND TIMING OF THE
SHORTWAVE ENTERING SOUTHWEST CANADA EARLY IN THE PERIOD WORKING
INTO SOUTHWEST CANADA THE CORRESPONDING SFC AREA OF LOW PRESSURE
SHOULD TRACK INTO QUEBEC WITH THE TRAILING COLD FRONT GRADUALLY
DROPPING SOUTH OF THE GREAT LAKES DURING THE MONDAY INTO TUESDAY
PERIOD...BEFORE STALLING OUT AND BECOMING NEARLY STATIONARY NEAR
THE OHIO RIVER. THE SHORTWAVE MOVING INTO THE MS VALLEY AROUND
MIDWEEK SHOULD LEAD TO A SFC WAVE OR WAVES DEVELOPING ALONG THIS
BOUNDARY AND MOVING THROUGH THE OHIO VALLEY REGION. THE FRONTAL
ZONE ITSELF COULD ALSO PASS THROUGH THE AREA LATE IN THE PERIOD.
OVERALL...THE EXPECTED SFC AND UPPER AIR PATTERN WILL LEAVE THE
REGION SUSCEPTIBLE TO AT LEAST DIURNALLY DRIVEN CONVECTION AND
POSSIBLE MCS OR NOCTURNAL ACTIVITY. THE NORTHERN AND EASTERN PARTS
OF THE AREA MAY BE IMPACTED EARLY IN THE WEEK...POSSIBLY AS EARLY
AS THE START OF THE WORK WEEK.
AS FOR POPS...SUNDAY IS EXPECTED TO BRING A DRY END TO THE WEEKEND.
ISOLATED TO SCATTERED CONVECTION CANNOT BE RULED OUT AT ANY POINT
FROM MONDAY TO POSSIBLY AS LATE AS FRIDAY. THE TRACK AND TIMING OF
THE SHORTWAVE THAT ENTERS SW CANADA EARLY IN THE PERIOD WILL PLAY
A KEY ROLE IN THE DURATION OF THE THREAT FOR CONVECTION. WITH THE
MODELS RELATIVELY IN GOOD AGREEMENT THROUGH ABOUT THURSDAY WITH
THE SFC AND UPPER AIR PATTERN AND THE SHORTWAVE EXPECTED TO NEAR
AT MIDWEEK...CHANCES FOR CONVECTION APPEAR GREATEST FROM WED INTO
THU.
TEMPERATURES SHOULD MODERATE TO A FEW DEGREES ABOVE NORMAL DURING
THE MONDAY INTO WEDNESDAY PERIOD...BEFORE THE COLD FRONT GRADUALLY
SLIPS SOUTH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 230 AM EDT SAT AUG 1 2015
HIGH PRESSURE WILL KEEP VFR CONDITIONS IN THE TAF FORECAST FOR
MOST OF THE SITES THROUGH THE PERIOD. THE EXCEPTION MAY BE AT SME
LATE THIS NIGHT AS THEIR DEWPOINT DEPRESSION IS CURRENTLY THE
SMALLEST. ACCORDINGLY...HAVE ADDED A PERIOD OF MVFR FOG TO THAT
SITE WHILE LEAVING THE REST CLEAN. OUTSIDE OF THE FORMAL TAF
SITES...PATCHY FOG WILL BE FOUND IN THE LOWER ELEVATIONS TOWARDS
DAWN...BECOMING LOCALLY DENSE FOR A BRIEF TIME. ANY FOG WILL
CLEAR OUT BY MID MORNING WITH VFR CONDITIONS CONTINUING INTO
SATURDAY NIGHT AT THE AIRPORTS. WINDS THROUGH THE PERIOD WILL BE
LIGHT AND VARIABLE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...JP
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
555 AM EDT SAT AUG 1 2015
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA TODAY...BRINGING ANOTHER THREAT
FOR SHOWERS AND THUNDERSTORMS. TEMPERATURES AND HUMIDITY DROP OFF
A LITTLE MORE BEHIND THIS FRONT. SUNDAY SHOULD BE MAINLY DRY AS
HIGH PRESSURE BUILDS ACROSS NEW ENGLAND. WEAK LOW PRESSURE
ALOFT...SITUATED OVER QUEBEC...WILL BRING ANOTHER ROUND SHOWERS OR
STORMS MONDAY AFTERNOON INTO TUESDAY. THE MID TO LATE WEEK PERIOD
WILL REMAIN UNSETTLED WITH A FEW ROUNDS OF SHOWERS OR
THUNDERSTORMS POSSIBLE.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
553AM UPDATE: WILL DIMINISH EARLY MORNING POPS SOME BASED ON
WEAKENING RADAR TREND SEEN WITH INITIAL ECHOES AS THEY ATTEMPT TO
WORK THROUGH NORTHERN VERMONT AND OUTRUN ANY MEANINGFUL MUCAPE
FROM RECENT RAP ANALYSES. EXPECT THAT WE/LL NEED A LITTLE MORNING
SUN AND RESULTANT INSTABILITY TO GET ACTIVITY TO INCREASE IN
COVERAGE/INTENSITY. HAVE ALSO LOWERED TEMPS SOME AND INCLUDED SOME
FOG THROUGH 12Z BASED ON EARLY MORNING OBSERVATIONS SHOWING
LOCALLY DENSE FOG IN THE NORTHERN VALLEYS.
HIGH IMPACT WEATHER POTENTIAL: ISOLATED SEVERE THUNDERSTORM
POTENTIAL THIS AFTERNOON FOR NORTHERN NH AND NORTHERN MAINE.
CURRENT PATTERN: CYCLONIC FLOW THROUGH THE COLUMN HAS FULLY
ENVELOPED THE REGION AS OF THIS WRITING WITH EARLY MORNING WATER
VAPOR IMAGERY SHOWING VERTICALLY STACKED LOW CENTERED OVER HUDSON
BAY. A PARADE OF LOCAL VORTICITY MAXIMA CAN ALSO BE SEEN ROTATING
AROUND THIS FEATURE...WITH A BAND OF ENHANCED MOISTURE STRETCHING
FROM CENTRAL ONTARIO SOUTH AND EAST ACROSS THE NORTHERN GREAT
LAKES...AND JUST STARTING TO SCRAPE NORTHERN NEW ENGLAND. A
SHORTWAVE IS COLLOCATED WITH THE LEADING EDGE OF THIS
MOISTURE...WITH A SURFACE COLD FRONT SPARKING A FEW SHOWERS /AND
EMBEDDED THUNDER/ ACROSS NEW YORK INTO FAR WESTERN NEW ENGLAND.
THE INITIAL SHORTWAVE NORTH OF NEW ENGLAND WILL CONTINUE TO RIDE
NORTH AND EAST...MAKING WAY FOR ANOTHER WAVE...NOW OVER SOUTHERN
ONTARIO...TO PULL EAST AND BE THE FOCUS FOR OUR SENSIBLE WEATHER
TODAY. FORECAST CHALLENGES CENTER AROUND PRECIPITATION POTENTIAL
WITH THIS FEATURE AS WELL AS THE POTENTIAL FOR ANY STRONG/SEVERE
CONVECTION.
THROUGH DAYBREAK: SHOWERS SEEN ON REGIONAL 88D MOSAIC CONTINUE TO
MAKE A RUN AT NORTHERN NEW HAMPSHIRE. EXPECT THAT WE/LL HAVE TO
WAIT FOR THE ACTIVITY IN NEW YORK TO MOVE INTO THE REGION FOR ANY
APPRECIABLE PRECIPITATION...WITH PERHAPS A SPRINKLE POSSIBLE OVER
COOS COUNTY NH THROUGH DAYBREAK. OTHERWISE...JUST SOME MID LEVEL
CLOUDS AND TEMPERATURES RANGING FROM THE LOWER 50S NORTH THROUGH THE
LOWER 60 OVER SOUTHERN NH.
TODAY: ATTENTION TURNS TO UPSTREAM PV ANOMALY MENTIONED ABOVE. THIS
FEATURE LOOKS TO SHARPEN AS IT ROUNDS THE BASE OF THE LONGWAVE
TROUGH AND PUSH INTO NEW ENGLAND. THIS FEATURE WILL BE ACCOMPANIED
BY 50KT JET AT H5 WITH A 1.5PV 85KT SPEED MAX. MODEST HEIGHT FALLS
AND INCREASING DPVA WILL WORK IN TANDEM WITH MODEST MOISTURE
INCREASE AND GOOD LAPSE RATES THROUGH H5 /GIVEN COOL POOL ALOFT/
TO ALLOW CONVECTION CURRENTLY OVER NEW YORK TO EXPAND AS IT MOVES
THROUGH NORTHERN NEW ENGLAND...BEING JOINED LATER BY ADDITIONAL
DEVELOPMENT AHEAD OF THE MID LEVEL TROUGH AXIS/WEAK SURFACE FRONT.
THUS...EXPECT SHRAS TO EXPAND IN COVERAGE...WITH EMBEDDED THUNDER
BECOMING MORE WIDESPREAD AS INSTABILITY GROWS. DEEP LAYER SHEAR IS
IMPRESSIVE...APPROACHING 50KTS IN THE 0-6KM LAYER WITH
LONG AND STRAIGHT...WEST-EAST ORIENTED HODOGRAPHS FAVORING MORE
CELLULAR STRUCTURE TO CELLS GIVEN ORTHOGONAL ORIENTATION OF THE
SHEAR TO THE FORCING FEATURE /FRONT/. INSTABILITY WILL BE
SOMEWHAT LIMITED GIVEN ONLY MODEST LLEVEL MOISTURE RECOVERY...BUT
1K J/KG MLCAPE APPEARS POSSIBLE TO ATTAIN OVER FAR NORTHERN NH /
NW MAINE CLOSER TO THE BEST MID LEVEL LAPSE RATES.
SEVERE WEATHER THREATS: PROFILES HAVE AN INVERTED-V LOOK TO
THEM...WHICH...WITH STRONG WINDS ALOFT SUGGEST A DAMAGING WIND
THREAT...ALTHOUGH MORE LOCALIZED GIVEN THE MORE CELLULAR NATURE TO
THE CONVECTION. WET BULB ZERO HEIGHTS 8-9KFT HIGHLIGHT A HAIL
THREAT AS WELL. TOR THREAT VERY LOW GIVEN THE AFOREMENTIONED
INVERTED-V PROFILES. OVERALL THREAT WILL BE TIED PRIMARILY TO
INSTABILITY...AND THEREFORE WILL BE GREATEST OVER FAR NORTHERN NH
AND NW MAINE...WHICH IS RIGHT IN LINE WITH THE NEW SWODY1 FROM SPC.
WILL INCLUDE ENHANCED WORDING IN THESE LOCATIONS...WITH LESS THUNDER
EMPHASIS FURTHER SOUTH. AND...WHILE THE ACTIVITY FURTHER SOUTH
WILL LIKELY NOT BE SEVERE...WILL MENTION GUSTY WINDS HERE AS WELL
GIVEN INVERTED-V NATURE TO THE PROFILES.
TEMPERATURES: THE INCREASE IN CLOUD COVER WILL SPELL A COOLER
DAY...PARTICULARLY OVER NORTHERN AREAS WHERE CONVECTION WILL BE MOST
WIDESPREAD. HERE...HIGHS WILL REMAIN IN THE 70S. DOWNSLOPE
WESTERLIES WILL PROMOTE HIGHS WELL INTO THE 80S OVER SOUTHEASTERN NH
AND EXTREME SW MAINE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
HIGH IMPACT WEATHER POTENTIAL: NONE.
PATTERN/IMPLICATIONS: WESTERLY FLOW ALOFT WILL CONTINUE THROUGH
THE SHORT TERM FORECAST PERIOD ALONG THE SOUTHERN PERIPHERY OF
LONGWAVE TROUGH CENTERED OVER HUDSON BAY. OUR WEATHER WILL BE AT
THE MERCY OF SHORTWAVES ROTATING AROUND THIS FEATURE...WITH A
RELATIVE LULL LIKELY FOR TONIGHT-SUNDAY BEHIND THE STRONGER WAVE
ON SATURDAY AND PRECEDING ANOTHER STRONG WAVE ON MONDAY. DESPITE
RELATIVELY LOW HEIGHTS IN THE TROUGH...LLEVEL TEMPERATURES WILL
REMAIN NEAR NORMAL PROMOTING SURFACE TEMPERATURES NOT TOO FAR FROM
SEASONAL NORMS.
TONIGHT: ANY AFTERNOON CONVECTIVE ACTIVITY SHOULD VERY QUICKLY WANE
WITH PARTIAL CLEARING...ALTHOUGH WITH DEEPER MOISTURE POOL CLOSER TO
THE REGION...DO EXPECT SOME MID LEVEL CLOUDINESS TO HANG AROUND
THROUGH THE NIGHT. LOWS LOOK NOT ALL THAT DISSIMILAR TO TONIGHT
WITH MODEST COOLING TO THE LLEVEL AIRMASS BEHIND DEPARTING COLD
FRONT. GIVEN AT LEAST SOME RAIN ACROSS THE REGION...AND ONLY MODEST
COOLING BEHIND THE DEPARTING COLD FRONT...SOME PATCHY VALLEY FOG
LOOKS TO BE A GOOD BET.
SUNDAY: DEEP CYCLONIC FLOW CONTINUES ACROSS THE REGION AND WHILE
THERE WILL BE LITTLE IN THE WAY OF SYNOPTIC FORCING FOR ASCENT...MID
LEVEL COLD POOL /T5S NEAR -15C/ AND DECENT MOISTURE ALONG SOUTHERN
PERIPHERY OF THE HUDSON BAY VORTEX WILL LIKELY ALLOW SOME AFTERNOON
SHOWERS TO SPARK OVER THE MOUNTAINS. ACTIVITY LOOKS WEAKER AND FAR
LESS WIDESPREAD THAN ON SATURDAY...SO REALLY NOT A BAD DAY EVEN UP
NORTH. OVER SOUTHERN NH/SOUTHWEST MAINE...EXPECT A DIURNAL INCREASE
IN CLOUDS...BUT NO PRECIPITATION. TEMPS ALOFT WILL BE ABOUT 2C
COOLER THAN ON SATURDAY...BUT WITH LIKELY A BIT MORE SUN...SO HIGH
TEMPERATURES LOOK SIMILAR TO THE DAY PREVIOUS...PERHAPS A DEGREE/TWO
COOLER FOR SOUTHEAST NH AND SW MAINE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGH IMPACT WEATHER IN THE EXTENDED WILL BE THREAT OF STRONG TO
SEVERE THUNDERSTORMS MONDAY AFTERNOON INTO MONDAY NIGHT.
500MB PATTERN IS TRENDING TOWARD A MODIFIED +PNA PATTERN WITH
CLOSED LOW STARTING OUR OVER HUDSON AROUND 60N AND EVENTUALLY
SHIFT SWD INTO SRN QUEBEC BY MID WEEK BEFORE SHIFTING THE NE AND
WEAKENING AS IT RUNS INTO N ATLANTIC RIDGING. THIS WILL PULL SOME
COOLER AIR SWD BY MID TO LATE THIS WEEK...AND WILL KEEP THINGS
SOMEWHAT UNSETTLED AS IT PRODUCES CYCLONIC FLOW ALOFT. TOWARD NEXT
WEEKEND THE CORE OF THE JET WILL SHIFT BACK TO THE N...AND COULD
SEE THINGS START TO WARM AGAIN.
SUN NIGHT WILL START WITH BUILDING 500MB RIDGING OVER ME AN THE
CANADIAN MARITIMES WHICH WILL ALLOW FLOW TO SHIFT TO THE SW ANDTAP
INTO WARM AIR...SFC AND MID-LVL JUST TO OUR SW. AFTER AN MAINLY
CLEAR AND SEASONABLY COOL SUN NIGHT MONDAY WILL WARM UP WITH
SHRA/TSRA MOVING INTO NW ZONES IN THE AFTERNOON. AS THE 500 MB
CLOSED LOW DEEPENS TO THE WEST AND HEIGHTS FALL WILL SEE DECENT
INSTABILITY DEVELOP ALONG WITH INCREASED FLOW ALOFT. NAM IS
SUGGESTING BORDERLINE EML MOVING IN OVER THE COASTAL PLAIN BY LATE
MON AFT INTO MON EVE...WHICH WOULD AID IN THE FORMATION OF SEVER
STORMS. AT ANY RATE THUNDERSTORMS...WILL BE A GOOD BET AWAY FROM
THE COAST MON AFTERNOON INTO EVENING. ANOTHER WEAK WAVE SWINGS
AROUND THE CLOSED LOW ON TUE...SO ANOTHER ROUND OF SHRA AND TSRA
POSSIBLE...AS THE COOLER AIR WILL WORK IN BEHIND THIS WAVE
TUESDAY. WED THRU FRI WILL BE PARTLY SUNNY...BUT COLD AIR ALOFT
COULD PRODUCE SCT SHRA...MAYBE A TSRA EACH DAY...ESPECIALLY IN THE
MTNS.
TEMPERATURES WILL START OUT ON THE WARM SIDE MONDAY...AS HIGHS
WILL SURGE BACK INTO THE 85-90 RANGE IN MANY INLAND SPOTS...BUT
SHOULD BE A FEW DEGREES COOLER ON THE COAST...AND ESPECIALLY THE
MID-COAST WHERE SW FLOW INCREASES. IT WILL BE A WARM AND MUGGY MON
NIGHT...WITH TEMPS AND HUMIDITY ON THE HIGHER SIDE TUE...BUT MORE
CLOUDS WILL KEEP TEMPS DOWN A FEW DEGREES. ONCE THE FRONT COMES
THRU IN THE AFTERNOON LOOK FOR OVERNIGHT LOWS TO DROP TO AROUND
NORMAL...LOW-MID 50S N...TO THE LOW 60S IN SRN NH...WITH HIGHS
RUNNING IN THE LOW 70S TO AROUND 80 THRU THE REST OF THE WEEK.
&&
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH 06Z SAT/...GENERALLY VFR WITH SOME INCREASING
MID LEVEL CLOUDINESS THROUGH DAYBREAK /ESPECIALLY NORTH/...WITH
SOME PATCHY GROUND FOG AT HIE BRINGING OCCASIONAL MVFR VSBYS.
FOR THE DAY ON SATURDAY...A MID LEVEL DISTURBANCE MOVING INTO THE
REGION WILL RESULT IN INCREASING CLOUDS WITH SCATTERED TO NUMEROUS
SHOWERS AND THUNDERSTORMS DEVELOPING ACROSS NORTHERN NEW HAMPSHIRE
AND NORTHWESTERN MAINE DURING THE LATE MORNING HOURS AND CONTINUING
THROUGH THE AFTERNOON...WITH MORE ISOLATED ACTIVITY FURTHER SOUTH.
THERE WILL LIKELY BE A FEW TEMPORARY PERIODS OF MVFR VSBYS/CIGS...
WITH IFR VSBYS POSSIBLE IN A FEW DOWNPOURS...BUT THE DAY WILL REMAIN
LARGELY VFR. LEB/HIE/AUG/RKD STAND THE BEST CHANCE OF SEEING
STORMS...WHICH COULD BE POTENTIALLY STRONG. ANY CONVECTION WILL
QUICKLY WANE DURING THE EVENING WITH PARTIAL CLEARING EXPECTED.
WINDS: CALM-LIGHT/VARIABLE WINDS THROUGH DAYBREAK WILL BECOME WEST-
SOUTHWESTERLY 10G18KTS FOR THE DAY ON SATURDAY BEFORE BECOMING LIGHT
WEST-NORTHWESTERLY /5KTS OR LESS/ SATURDAY EVENING.
EXPECT VFR CONDITIONS ON SUNDAY...WITH A DIURNAL INCREASE IN
CUMULUS COVERAGE...AND PERHAPS A SPRINKLE/SHOWER AT HIE.
LONG TERM...MAINLY VFR SUN NIGHT THROUGH TUESDAY...WITH VLY FOG
POSSIBLE EACH NIGHT. SCT SHRA/TSRA WILL IMPACT MOST OF THE
TERMINALS LATE MON AND MON NIGHT.
&&
.MARINE...
SHORT TERM...EXPECT WAVES AND SOUTHERLY WINDS TO REMAIN BELOW
SMALL CRAFT LEVELS THROUGH SUNDAY DESPITE INCREASING SOMEWHAT
DURING THE DAY TODAY AHEAD OF A COLD FRONT.
LONG TERM...PERSISTENT SW FLOW SUNDAY AND MONDAY COULD BRING
HIGHER SWELLS TO THE COASTLINE MONDAY AND MONDAY NIGHT....AND A
SURGE OF SW WINDS COULD APPROACH SCA LVLS FOR A SHORT PERIOD MON
NIGHT.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...ARNOTT
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
AREA FORECAST DISCUSSION
NWS CARIBOU ME
127 AM EDT SAT AUG 1 2015
.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL BUILD ACROSS THE AREA OVERNIGHT.
UPPER LEVEL DISTURBANCES CROSSING THE REGION WILL KEEP UNSETTLED
CONDITIONS THROUGH THE WEEKEND WITH SCATTERED SHOWERS AND
THUNDERSTORMS.
&&
.NEAR TERM /THROUGH SATURDAY/...
115 AM UPDATE...ADJUSTED THE POPS THROUGH 12Z TO BRING 20% ACROSS
THE W AND NW AREAS. THE LATEST HRRR 3KM MODEL MATCHED UP W/THE
LATEST RADAR TRENDS BRINGING LIGHT RETURNS(25-30DBZ) ACROSS THE
AFOREMENTIONED AREAS EARLY THIS MORNING. WX ELEMENT WILL BE LIGHT
SHOWERS. IR SATL IMAGERY SHOWED SOME CLOUDS MOVING ACROSS QUEBEC
TOWARD WNW AREAS. OBS AND CEILING PLOTS INDICATE CLOUD DECK
BETWEEN 5 AND 8K FT. 05Z SFC ANALYSIS HAD WEAK RIDGE MOVING E
W/WEAK COLD FRONT MOVING TOWARD QUEBEC. TEMPS WERE ADJUSTED AS
WELL TO MATCH THE LATEST CONDITIONS.
GENERALLY EXPECT PARTLY CLOUDY/MOSTLY CLEAR SKIES ACROSS NORTHERN
PORTIONS OF THE FORECAST AREA OVERNIGHT...THOUGH CLOUD COVER WILL
BEGIN TO INCREASE ACROSS NORTHWEST AREAS LATE IN ADVANCE OF THE
APPROACHING UPPER DISTURBANCE. MOSTLY CLEAR SKIES WILL OCCUR
ACROSS THE REST OF THE FORECAST AREA OVERNIGHT. OVERNIGHT LOW
TEMPERATURES WILL RANGE FROM THE UPPER 50S TO AROUND 60 ACROSS THE
FORECAST AREA. HAVE UPDATED THE FORECAST TO ADJUST FOR CURRENT
CONDITIONS ALONG WITH EXPECTED OVERNIGHT TEMPERATURES AND CLOUD
COVER.
THE FOCUS FOR SATURDAY DEAL W/UPPER TROUGH & COLD FRONTAL
PASSAGE. EXPECT SHOWERS AND THUNDERSTORMS TO DEVELOP ALONG AND
JUST AHEAD OF THE SURFACE FRONT/WIND SHIFT LINE EARLY IN THE
AFTERNOON AND THEN SHIFT SOUTHEAST THROUGH THE EVENING HOURS. IT
LOOKS LIKE THINGS SHOULD FIRE UP A LITTLE EARLIER THAN PREVIOUSLY
ANTICIPATED, WITH SHOWERS AND THUNDERSTORMS MOVING INTO THE FAR
NORTHWEST BY EARLY AFTERNOON AND INTO INTERIOR DOWNEAST BY EARLY
EVENING. 0-6KM SHEAR LOOKS GOOD AT 40-45 KT, ALONG WITH MID-LEVEL
LAPSE RATES 5.5-6.5 C/KM. ALTHOUGH SOME OF THE MODELS INDICATE SB
CAPES OF 1100+J/KG, THIS IS LIKELY OVERDONE AND THE MORE MODEST
600-1000 J/KG SEEMS MORE REASONABLE. THIS ALONG WITH A DRY LAYER
ALOFT COULD SERVE TO LIMIT SEVERE POTENTIAL. THE BIGGEST THREAT
WOULD BE HAIL GIVEN THE COLD AIR ALOFT, THOUGH GUSTY WINDS WILL BE
POSSIBLE IN ANY STORMS THAT ARE ABLE TO TAP THE STRONGER WINDS
ALOFT. THIS THINKING FOLLOWS CLOSELY WITH SPC, WHICH HAS CONTINUED
TO INCLUDE ALL OF INTERIOR MAINE IN A MARGINAL SEVERE RISK IN
THEIR LATEST DAY 2 OUTLOOK. HAVE THEREFORE KEPT ENHANCED WORDING
IN TOMORROW`S FORECAST.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
UNSETTLED WEATHER WILL CONTINUE ACROSS PINE TREE STATE...WITH A
WEAK SHORTWAVE AFFECTING OUR CWA ON SUNDAY...AND THEN A STRONG
UPPER LOW SWINGING EWD ACROSS NEW ENGLAND. THE FEATURES WILL
PRODUCE THEIR OWN ROUND OF SHOWERS AND TSTORMS...WITH THE SECOND
HAVING MORE WIDESPREAD AND HEAVIER PRECIP. TEMPERATURES WILL BE
SEASONABLY WARM WITH HIGHS RANGING FROM THE MID 70S TO THE LOWER
80S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A TROUGH DIGGING INTO EASTERN CANADA WILL SET THE STAGE FOR SOME
COOLER WEATHER COMING IN DURING THE MID WEEK PERIOD. A COLD FRONT
COMING THROUGH MONDAY NIGHT WILL BRING A CHANCE FOR SHOWERS AND
SCATTERED THUNDERSTORMS. THE AIR BEHIND THIS COLD FRONT WILL ONLY
BE SLIGHTLY COOLER AND DRIER ON TUESDAY. SIGNIFICANTLY COOLER AIR
WILL THEN FILTER INTO THE AREA TUESDAY NIGHT INTO WEDNESDAY AS A
TROUGH OF LOW PRESSURE BEGINS DROPPING SOUTHEAST ACROSS QUEBEC.
SOME ISOLATED SHOWERS WILL BE POSSIBLE ACROSS THE NORTH ON
WEDNESDAY. THE TROUGH WILL BEGIN TO LIFT AWAY TO THE NORTHEAST ON
THURSDAY ALLOWING FOR A DRY DAY WITH SUNSHINE AND TEMPS A FEW
DEGREES BELOW NORMAL. DRY WEATHER MAY LAST INTO FRIDAY BEFORE A
DEEPER AND STRONGER TROUGH APPROACHES OVER THE WEEKEND BRINGING A
CHANCE FOR SHOWERS SATURDAY THEN A TREND TOWARD COOLER CONDITIONS
SUNDAY INTO MONDAY.
&&
.AVIATION /05Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: VFR CONDITIONS ARE EXPECTED OVERNIGHT INTO EARLY
SATURDAY. HOWEVER...SHOWERS AND THUNDERSTORMS WILL DEVELOP BY
EARLY AFTERNOON ALONG A COLD FRONT AND CROSS FROM NORTHWEST TO
SOUTHEAST DURING THE AFTERNOON/EVENING. MVFR AND EVEN LOCAL IFR
CONDITIONS WILL BE POSSIBLE IN ANY CONVECTION ALONG WITH GUSTY
WINDS AND SMALL HAIL.
SHORT TERM: SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED
ACROSS MUCH OUR FCST AREA SUNDAY AND MONDAY. REDUCED CIGS AND
VSBYS WILL PROBABLY ACCOMPANY THE STRONGER SHOWERS AND STORMS.
ALSO...STRONG WINDS...FREQUENT LIGHTNING AND HEAVY DOWNPOURS ARE
POSSIBLE WITH THE STRONGER STORMS ON MONDAY.
&&
.MARINE...
NEAR TERM: WINDS/SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
LEVELS OVERNIGHT THROUGH SATURDAY.
SHORT TERM: WINDS AND WAVE HEIGHTS WILL STAY BELOW SCA CRITERIA
DURING SATURDAY NIGHT THROUGH MONDAY. HOWEVER SOME THUNDERSTORM
ACTIVITY MAY AFFECT COASTAL MARINE ZONES ON MONDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HEWITT
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
343 AM CDT SAT AUG 1 2015
.SHORT TERM: (THROUGH TONIGHT)
ISSUED AT 340 AM CDT SAT AUG 1 2015
SCATTERED THUNDERSTORMS HAVE RECENTLY DEVELOPED OVER NORTHEAST
MISSOURI AND WEST CENTRAL ILLINOIS IN AN SMALL AREA OF LOW LEVEL
MOISTURE CONVERGENCE. RECENT RUNS OF THE RAP SHOW THIS FORCING
ERODING AROUND 12Z. ATMOSPHERE WILL BECOME UNSTABLE AGAIN THIS
AFTERNOON...HOWEVER THERE WILL BE LITTLE IN THE WAY OF FORCING FOR
IT TO ACT ON. HAVE KEPT CHANCE POPS OVER NORTHEAST MISSOURI AND
WEST CENTRAL ILLINOIS...PARTICULARLY OVERNIGHT AS A SHORTWAVE TROUGH
WILL MOVE THROUGH THE UPPER MIDWEST WHICH WILL LIKELY PUSH A MCS
ALONG A FRONTAL BOUNDARY OVER IOWA INTO INTO THE NORTHERN CWA.
SHOULD BE ANOTHER WARM DAY ACROSS THE AREA WITH 850MB TEMPERATURES
BETWEEN 18-20C. HIGH TEMPERATURES SHOULD CLIMB BACK INTO THE LOW-
MID 90S WITH MIXING UP TO 850MB.
BRITT
.LONG TERM: (SUNDAY THROUGH FRIDAY)
ISSUED AT 340 AM CDT SAT AUG 1 2015
(SUNDAY AND MONDAY)
WILL CONTINUE THE CHANCE OF THUNDERSTORMS ON SUNDAY AS THE COLD
FRONT MOVES DOWN INTO THE AREA. CHANCES WILL BE LOWER ON SUNDAY
NIGHT AND MONDAY AS CONVERGENCE WEAKENS ALONG THE FRONT AS IT MOVES
TO THE SOUTHWEST UNDER NORTHWESTERLY FLOW ALOFT. BOTH DAYS WILL
CONTINUE TO BE WARM WITH MOS TEMPERATURES IN THE LOW-MID 90S AND
850MB TEMPERATURES REMAINING NEAR 20C.
(TUESDAY THROUGH FRIDAY)
IT STILL LOOK LIKE MID TO LATE NEXT WEEK WILL BE UNSETTLED WITH A
CONTINUED CHANCE OF SHOWERS AND THUNDERSTORMS IN NORTHWEST FLOW
ALOFT. BEST CHANCE WILL BE TUESDAY INTO WEDNESDAY WHEN BOTH THE GFS
AND ECMWF SHOW A NOTABLE TROUGH MOVING THROUGH MISSOURI AND
ILLINOIS. TEMPERATURES WILL FALL BACK BELOW NORMAL AS 850MB
TEMPERATURES ARE FORECAST TO BE AROUND 15C.
BRITT
&&
.AVIATION: (FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1134 PM CDT FRI JUL 31 2015
A FEW SHOWERS STILL REMAIN NEAR KUIN TONIGHT AND WILL HAVE TO KEEP
AN EYE ON THIS AREA OVER THE NEXT FEW HOURS. OTHERWISE...A MOSTLY
DRY FORECAST IS IN STORE WITH LIGHT WESTERLY WINDS THROUGH
SATURDAY EVENING. A COMPLEX OF THUNDERSTORMS IS EXPECTED TO
DEVELOP LATE SATURDAY AFTERNOON/EVENING ACROSS THE MID-MISSOURI
VALLEY AND TRACK EASTWARD OVERNIGHT SATURDAY NIGHT. QUINCY MAY BE
AFFECTED TOWARD OR AFTER 0600 UTC BUT LEFT OUT OF TAF FOR NOW
SINCE IT IS SO LATE IN THE PERIOD.
SPECIFICS FOR KSTL:
FEW SHOWERS AND MAYBE A STORM WELL TO THE NORTH OF THE TERMINAL
SHOULD WEAKEN/DISSIPATE BEFORE REACHING THE AREA LATER TONIGHT.
OTHERWISE...LIGHT WINDS PREDOMINANTLY OUT OF THE WEST WILL
CONTINUE THROUGH SATURDAY NIGHT WITH DRY WEATHER AND PARTLY CLOUDY
SKIES ALSO EXPECTED.
GOSSELIN
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
313 AM CDT Sat Aug 1 2015
...Quiet Weather Pattern This Weekend...An Unsettled Weather
Pattern Returns Middle of Next Week...
.SHORT TERM...(Today and Tonight)
Issued at 254 AM CDT SAT AUG 1 2015
It is a fairly quiet morning across the Missouri Ozarks with
mostly clear skies and temperatures rather pleasant in the lower
to middle 60s. Today will be almost a carbon copy of yesterday`s
weather. Temperatures will be in the lower 90s. Humidity values
will still be rather low which means the heat index will be near
the actual air temperature. The latest HiRes short term models
like the HRRR and ARW show a very small potential for a spotty
shower developing this afternoon across the central Missouri area
down into the eastern Ozarks. Not sold on this potential at this
time and will only leave in a silent 10 percent chance for this
happening this afternoon.
.LONG TERM...(Sunday through Friday)
Issued at 254 AM CDT SAT AUG 1 2015
For the end of the weekend into early next week...The upper level ridge
remains west of the region with the center near the west Texas
area and the Missouri Ozarks region will be in a northwest flow.
Southerly winds at the surface will help bring back the humidity
and low level moisture. Temperatures will gradually increase a
degree or two each day with most areas reaching the lower to
middle 90s by Monday. The heat index will climb back into the
upper 90s to around 100 possible.
The weather pattern becomes somewhat unsettled by the middle of
next week. The first of a couple mid level shortwaves will move
across the top of the ridge over the western U.S. early next week.
This shortwave looks fairly decent and will impact the area on
Tuesday afternoon through Wednesday morning. The latest guidance has
moved up the timing a little bit since the previous runs. A weak
frontal boundary also will be stalled out across the Missouri
Ozarks for the middle of next week.
Another impulse will affect the area late Thursday into Friday.
Will not get too specific with timing this far out but it does
appear that there will be several rounds of thunderstorms possible
Tuesday through Friday for the area with a more active weather
pattern likely. Temperatures will also be slightly lower for the
middle and end of next week with highs in the middle to upper 80s.
Overall average rainfall will be in the 1 to 2 inch range for next
week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Saturday Night)
Issued at 1134 PM CDT FRI JUL 31 2015
VFR conditions and mostly clear skies will continue into Saturday
evening. Winds will remain light and variable.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Schaumann
AREA FORECAST DISCUSSION
NWS HASTINGS NE
428 AM CDT SAT AUG 1 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM CDT SAT AUG 1 2015
A FAIRLY CHALLENGING FORECAST THIS MORNING AS CONVECTION HAS
CONTINUED AND ACTUALLY ENHANCED ACROSS PORTIONS OF THE LOCAL
FORECAST AREA OVERNIGHT. WITH THE TRAINING OF THIS CONVECTION OVER
THE SAME AREAS THE PAST FEW HOURS...COULD EVENTUALLY SEE SOME
MINOR FLOODING IN SPOTS IF ADDITIONAL ACTIVITY DEVELOPS.
IN THE MEANTIME...EXPECT AN UPPER LEVEL DISTURBANCE STRETCHING
FROM WESTERN SOUTH DAKOTA ACROSS THE LOCAL FORECAST AREA THIS
MORNING TO CONTINUE TO SPARK SHOWER AND THUNDERSTORM ACTIVITY
ACROSS THE LOCAL AREA THROUGH THE REMAINDER OF THE MORNING HOURS.
WHILE MOST GUIDANCE IS DOING A VERY POOR JOB WITH THE ONGOING
CONVECTION...08Z HRRR SEEMS FAIRLY WELL INITIALIZED...AND HAVE
LEANED TOWARDS THIS SOLUTION IN THE MORNING FORECAST. AS A
RESULT...EXPECT ONGOING CONVECTION TO CONTINUE ACROSS THE
NORTHEASTERN QUADRANT OF THE LOCAL AREA THROUGH THE LATE MORNING
HOURS BEFORE DISSIPATING...WITH THE FOCUS THEN TURNING TO THE
NEXT DISTURBANCE...WHICH IS EXPECTED TO DROP TOWARDS THE LOCAL
AREA FROM SOUTH DAKOTA DURING THE MID TO LATE AFTERNOON HOURS.
WHILE THE COVERAGE AND TIMING FROM THIS DISTURBANCE IS
STILL A BIT UNCERTAIN...SEVERAL MODELS ARE PICKING UP ON THIS
FEATURE...BRINING CONFIDENCE THAT AT LEAST THE NORTHERN PORTIONS
OF THE FORECAST AREA WILL SEE ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS THIS EVENING. WITH CAPE BUILDING AHEAD OF THIS
DISTURBANCE AND AMPLE SHEAR IN PLACE...IN PART DUE TO THE
PRESENCE OF A NEAR STATIONARY FRONTAL BOUNDARY ACROSS THIS
AREA...EXPECT THE POTENTIAL FOR A FEW STRONG TO MARGINALLY SEVERE
STORMS DEVELOPING DURING THE LATE AFTERNOON AND EVENING HOURS.
TEMPERATURE WISE...EXPECT ANOTHER SEASONABLY WARM AFTERNOON ACROSS
THE REGION WITH MOST LOCATIONS THAT ARE ABLE TO CLEAR OUT BY
AFTERNOON EXPECTED TO SEE TEMPERATURES CLIMB INTO THE LOWER TO
MIDDLES 90S...WITH THE BEST CHANCE FOR MORE WIDESPREAD CONVECTION
ALSO EXPECTED DURING THE LATE AFTERNOON THROUGH EARLY EVENING
HOURS. WITH THE RIGHT PARAMETERS IN PLACE...A FEW STRONG TO SEVERE
STORMS APPEAR LIKELY...ESPECIALLY FOR THE NORTHEASTERN PORTIONS OF
THE FORECAST AREA.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 403 AM CDT SAT AUG 1 2015
BIGGEST CONCERNS FOR THE FORECAST PERIOD...CHANCES OF THUNDERSTORMS
MONDAY NIGHT THROUGH TUESDAY NIGHT THEN AGAIN MID WEEK.
MODELS IN RELATIVE AGREEMENT WITH LARGE SCALE FEATURES SO WILL USE
BLEND. GENERALLY IN A NORTHWEST FLOW PATTERN THROUGH THE PERIOD.
THIS TYPE PATTERN TYPICALLY MAKES IT TOUGH TO FORECAST THE SPEED AND
STRENGTH OF SYSTEMS MOVING THROUGH. SO...CONFIDENCE IS NOT THE
HIGHEST IN TIMING...COVERAGE OR EVEN CHANCES OF RAIN UNTIL WE GET 12
TO 24 HOURS AWAY FROM ANY RAIN EVENT.
NONE THE LESS...THE MODELS ARE FAIRLY CONSISTENT IN FORECASTING A
NEARLY STATIONARY BOUNDARY OVER THE FORECAST AREA FROM MONDAY ON.
ALSO...MODELS SUGGEST A SHORT WAVE AND ASSOCIATED JET STREAK WILL
TOP THE RIDGE AND MOVE OVER AN AREA BETWEEN THE DAKOTAS AND KANSAS
ON MONDAY NIGHT OR TUESDAY. THUS...WILL LEAVE CHANCES FOR
THUNDERSTORMS IN FORECAST. IF STORMS DEVELOP THEY APPEAR TO HAVE
ENOUGH INSTABILITY AND WEAK SHEAR THAT A FEW COULD PRODUCE SOME NEAR
SEVERE HAIL STONES AND PERHAPS SOME GUSTY WINDS.
IN BETWEEN ANY STORMS THAT DEVELOP...DRY AND WARM WEATHER IS
EXPECTED. TEMPERATURES SHOULD BE NEAR NORMAL THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1240 AM CDT SAT AUG 1 2015
PREVAILING VFR CONDITIONS ARE EXPECTED AT BOTH TERMINALS THROUGH
THE PERIOD WITH CLEARING SKIES AND LIGHT WINDS EXPECTED OVERNIGHT.
FOR SATURDAY...EXPECT INCREASING MID LEVEL CLOUDS AND THE CHANCE
FOR THE DEVELOPMENT OF SOME SHOWERS AND THUNDERSTORMS...WHICH MAY
IMPACT THE TERMINALS...AND COVERED THIS POSSIBILITY WITH A VCTS
FOR THE TIME BEING. OVERALL...A FAIRLY WEAK GRADIENT IS IN
PLACE...SO SOUTH TO SOUTHWESTERLY WINDS OF 10KTS OR LESS ARE
EXPECTED TOMORROW.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...ROSSI
LONG TERM...EDDY
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
340 AM CDT SAT AUG 1 2015
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 335 AM CDT SAT AUG 1 2015
CHANCE FOR SEVERE THUNDERSTORMS TODAY AND TONIGHT...THEN WARM
TEMPERATURES SUNDAY...ARE THE PRIMARY FORECAST CONCERNS.
CONVECTION TIED TO SOUTHWARD-ADVANCING SURFACE FRONT HAD CLEARED THE
SOUTHERN NEBRASKA AND IOWA BORDERS LATE LAST EVENING. THAT BOUNDARY
IS EXPECTED TO RETREAT NORTHWARD TODAY AS A WARM FRONT IN RESPONSE
TO LOWERING PRESSURES TO OUR NORTHWEST IN ADVANCE OF MID LEVEL
SHORTWAVE DIVING FROM THE NORTHERN ROCKIES INTO SOUTH DAKOTA THIS
AFTERNOON. STRONG MOISTURE ADVECTION WILL FOLLOW WARM FRONT IN
SOUTHERLY LOW LEVEL FLOW...AND WHEN COMBINED WITH POTENT AFTERNOON
HEATING...WILL PRODUCE MOST-UNSTABLE CAPES WELL OVER 2500 J/KG.
ENHANCED NORTHWESTERLY MID LEVEL FLOW ATTENDANT TO APPROACHING
SHORTWAVE WILL INDUCE STRONG 0-6KM BULK SHEAR ON THE ORDER OF 40KT
AS SOUTH TO SOUTHWEST SURFACE FLOW INCREASES. VEERING WIND PROFILES
WITH MAGNITUDE OF SHEAR VECTORS WILL BE SUPPORTIVE OF ROTATING
STORMS SUGGESTING ALL MODES OF SEVERE WILL BE POSSIBLE THIS
AFTERNOON...WITH TORNADO POTENTIAL HIGHEST NEAR WARM FRONT IN
NORTHEAST NEBRASKA AND SOUTHEAST SOUTH DAKOTA...AND ESPECIALLY NEAR
TRIPLE POINT WHERE SOUTHEASTERLY-ADVANCING TROUGH/DRYLINE INTERSECTS
WARM FRONT.
EXPECT STORMS CURRENTLY FIRING IN SOUTH CENTRAL SOUTH DAKOTA INTO
CENTRAL NEBRASKA TO GRADUALLY WORK EAST AND SOUTHEAST THIS
MORNING...WITH ISOLATED TO SCATTERED STORMS REACHING OUR WESTERN
CWA. BETTER CONVECTIVE CHANCES COME THIS AFTERNOON WHEN
INSTABILITY IS MAXIMIZED...WITH FOCUS GEARED TOWARD LOW LEVEL
CONVERGENCE ALONG WARM FRONT...WHICH SHOULD LIE ACROSS NORTHEAST
NEBRASKA INTO WEST CENTRAL IOWA. INCREASING LOW LEVEL JET DURING
THE EVENING WILL SUPPORT CONTINUED DEVELOPMENT OF CONVECTION WITH
PROPAGATION VECTORS SHOWING A SOUTHEAST PROGRESSION ACROSS PARTS
OF EASTERN NEBRASKA AND WESTERN IOWA. EXPECT MOST CONVECTION TO BE
WELL EAST OF WESTERN IOWA BY SUNRISE SUNDAY...BUT SOME LINGERING
INSTABILITY/STORMS ARE POSSIBLE IN THE MORNING IN SOUTHWEST IOWA.
MOST OF SUNDAY IS EXPECTED TO BE DRY AS WESTERLY LOW LEVEL FLOW
PREVAILS ACROSS MUCH OF OUR CWA DURING THE MORNING. HOWEVER LOW
LEVEL MOISTURE WILL TAKE SOME TIME BEFORE BEING SWEPT SOUTH. A COLD
FRONT IS FORECAST TO FOLLOW EXITING SHORTWAVE...REACHING INTERSTATE
80 BY EARLY AFTERNOON THEN CLEARING OUR SOUTHERN BORDER BY LATE
SUNDAY AFTERNOON. WESTERLY WIND COMPONENT POINTS TO TEMPERATURES
WELL INTO THE 90S OVER THE SOUTHERN HALF OF OUR CWA...BUT NORTHERLY
WINDS BEHIND THE FRONT SUGGEST HIGHS CLOSER TO 90 IN OUR NORTH. AND
WITH LOW LEVEL MOISTURE...DEW POINTS IN THE MID 60S...REMAINING OVER
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA SUNDAY AFTERNOON...MUCAPES
WILL AGAIN TOP 2500 J/KG AS FRONT INVADES. THUS WILL INTRODUCE SOME
SMALL THUNDERSTORM CHANCES IN OUR SOUTH THEN.
MONDAY MAY BRING A SIMILAR SCENARIO TO TODAY AS SUNDAY COLD FRONT
STALLS IN NORTHERN KANSAS SUNDAY NIGHT THEN RETREATS BACK NORTH INTO
EASTERN NEBRASKA AND WESTERN IOWA MONDAY. SHORTWAVE IN NORTHWEST
FLOW ALOFT WILL AGAIN LOWER PRESSURES IN THE HIGH PLAINS...INDUCING
SOUTHERLY LOW LEVEL FLOW AND MOISTURE RETURN INTO OUR AREA. WE
SHOULD AGAIN SEE CONVECTION FIRING NEAR AND NORTH OF THE WARM FRONT.
EXACT PLACEMENT OF THAT FRONT WILL NEED TO BE REFINED LATER...BUT
WILL HAVE AT LEAST A SLIGHT CHANCE FOR STORMS OVER MOST OF THE
CWA...WITH HIGHER CHANCES NEAR AND NORTH OF A COLUMBUS TO NEBRASKA
CITY AND CLARINDA LINE. SUFFICIENT INSTABILITY AND SHEAR...30-
40KT...AGAIN SUGGEST SOME SEVERE STORMS WILL BE POSSIBLE.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 335 AM CDT SAT AUG 1 2015
THERE WILL BE A CHANCE FOR THUNDERSTORMS MUCH OF NEXT WEEK AS
NORTHWEST FLOW ALOFT CONTINUES TO EJECT SHORTWAVES INTO THE NORTHERN
AND CENTRAL PLAINS. THERE IS SOME INDICATION UPPER RIDGE AXIS WILL
SHIFT INTO THE PLAINS FOR A SHORT TIME WEDNESDAY NIGHT...KEEPING
THAT PERIOD DRY...BUT WE QUICKLY GET BACK INTO THE UNSETTLED
NORTHWEST FLOW PATTERN LATE IN THE WEEK.
MONDAY FRONTAL BOUNDARY IS EXPECTED TO REMAIN IN OR NEAR OUR CWA
MONDAY NIGHT INTO TUESDAY BEFORE MORE DEFINED MID LEVEL WAVE SWEEPS
FRONT/MOISTURE TO OUR SOUTHEAST LATER TUESDAY NIGHT OR WEDNESDAY.
GFS SHOWS OUR AREA ON COOL SIDE OF FRONTAL SYSTEM ON TUESDAY...SO
SEVERE THREAT LOOKS MINIMAL. HOWEVER SEVERE POTENTIAL RETURNS BY
THURSDAY AFTERNOON WHEN MAIN STORM TRACK SHIFTS BACK TO THE NORTH
BRINGING LOW LEVEL MOISTURE AND SUPPORTIVE SHEAR PATTERN BACK INTO
OUR AREA.
TEMPERATURES THROUGH THE WEEK LOOK COOLER...AVERAGING THE LOWER 80S
MOST AREAS...AS CLOUDS/PRECIP/THERMAL PROFILE KEEP A LID ON WARMING.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1145 PM CDT FRI JUL 31 2015
WILL GENERALLY FOLLOW TRENDS FROM MOST RECENT HRRR MODEL RUNS.
SOME PATCHY FOG APPEARS POSSIBLE ESPECIALLY AFTER 09Z AND MAINLY
AROUND KOMA. BY MID TO LATE MORNING...SOUTH/SOUTHWEST WINDS SHOULD
INCREASE TO AROUND 10 KNOTS OR SO. THERE APPEARS TO BE A DECENT
CHANCE THAT A TSTM COMPLEX WILL DROP SOUTHEAST INTO NORTHEAST
NEBRASKA BY MID TO LATE MORNING AND THEN DEVELOP/MOVE SOUTHEAST.
ATTEMPTED TO TIME THIS WITH PROB30 GROUPS FOR NOW. MENTIONED SOME
VARIABLE GUSTY WINDS AT KOFK WHERE CONFIDENCE IS HIGHEST AND
ACTIVITY WILL LIKELY AFFECT THAT LOCATION FIRST.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS ELKO NV
249 AM PDT SAT AUG 1 2015
.SYNOPSIS...MONSOON MOISTURE WILL INLFUENCE THE LOCAL REGION.
CENTRAL NEVADA CAN ANTICIPATE THUNDERSTORMS TODAY...WHILE NORTHERN
NEVADA WILL MORE THAN LIKELY BE A SUNDAY EVENT. UNSETTLED WEATHER
EXPECTED THROUGH MIDWEEK.
&&
.SHORT TERM...TODAY THROUGH SUNDAY. THE SYNOPTIC PATTERN FEATURES
RIDGING TO THE EAST...WITH MOISTURE FLUX INBOUND FROM OUR NEIGHBOR
TO THE SOUTH. THERE IS A WEAK DISTURBANCE EMBEDDED IN THE H5
FLOW...WHICH SHOULD BE THE MAIN EVENT WITH THIS MONSOON EPISODE. THE
NAM AND THE HRRR BOTH DEPICT MOIST AND UNSTABLE AIR IMPACTING THE
LKN CWA THIS FORECAST PERIOD...WITH THE NAM BEING A BIT MORE
BULLISH WITH THE QPF. THE HRRR KICKS INTO GEAR AROUND 18Z SOUTH OF
HIGHWAY 50...WITH MERITED BUMPING UP POPS THIS PACKAGE...WHILE THE
GFS40 IS SLOW TO BRING THE QPF INTO THE LKN CWA TODAY...WHILE THE
NAM SPLITS THE DIFFERENCE. SUNDAY...EXPECT A ANOTHER ROUND OF
QPF...ALBEIT FURTHER NORTH. THE MODELS SEEM TO HAVE SOME MARKET
DIFFERENCES IN THE QPF FIELDS PAST 24 HRS...BUT THE GENERAL TREND
IS A SHIFT TO THE NORTH.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY. MODELS IN GENERAL
AGREEMENT ON THE BIG PIC THROUGH THE PERIOD...WITH NIGGLING
DIFFERENCES IN THE SMALLER FEATURES PRETTY THROUGHOUT THE LONG TERM.
LOWERS CONFIDENCE IN AN ACCURATE FORECAST...BUT PRECISION IS OKAY
STILL.
UPPER RIDGE MOVES ON EAST AND OPENS THE DOOR FOR MONSOON MOISTURE TO
PERSIST LATE SUNDAY AFTERNOON...BUT THIS SLUG OF MOISTURE WILL MOVE
NORTH IN THE SOUTHWESTERLY DRIER FLOW MOVING INTO THE AREA ATTENDANT
TO THE PACIFIC LOW TRYING TO ABUT THE COASTAL AREAS.
PWS AND INSTABILITY WILL BE SUFFICIENT FOR SHOWERS AND THUNDERSTORMS
OF AN ISOLATED NATURE THROUGH THE EARLIER AND MIDDLE PARTS OF THE
FORECAST RANGE...DWINDLING LATER IN THE PACKAGE. HAVE NOT
DIFFERENTIATED BETWEEN AREAS OF SHOWERS AND THUNDERSTORMS THIS FAR
OUT FOR SIMPLICITY`S SAKE...SO HAVE STAYED TO "TRW" WORDING.
THIS IS A HYBRID SITUATION WITH SOME DRY AND SOME WETTISH
THUNDERSTORMS. MOST STORMS WILL RAIN...AND SOME WILL HAVE BRIEF
HEAVY RAINS.
&&
.AVIATION...VFR THROUGH 12Z SUNDAY. INCREASING MOISTURE WILL ENABLE
THUNDERSTORMS AT NEAR KTPH AND KELY SATURDAY AFTERNOON INTO EVENING.
WINDS GENERALLY LIGHT BUT GUSTY AND ERRATIC NEAR STORMS AND VIRGA.
TYPICAL SUMMER PATTER.
&&
.FIRE WEATHER...THE LATEST SURFACE ANALYSIS HAS A WELL DEFINED
DOME OF HIGH PRESSURE OVER NM/CO AND A DEEP FETCH OF MOISTURE
RUNNING UP THE SIERRA MADRE OCCIDENTAL AND INTO THE DESERT
SOUTHWEST. EXPECTING THIS MOISTURE TO GRADUALLY WORK ITS WAY INTO
CENTRAL AND NORTHERN NEVADA. BUT BASICALLY ITS KNOCKING ON THE
BACK DOOR OF 457...AND ONCE UNSTABLE...IT SHOULD GET PRETTY
INTERESTING. THE ONLY FLY IN THE OINTMENT WOULD BE IF THE CLOUD
COVERAGE INHIBITS CONVECTIVE INITIATION.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
97/98/98/97
AREA FORECAST DISCUSSION
NWS BISMARCK ND
333 AM CDT SAT AUG 1 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CDT SAT AUG 1 2015
A VERY WARM DAY TODAY HIGHLIGHTS THE SHORT TERM FORECAST.
NORTHWEST UPPER LEVEL JET FLOW CONTINUED OVER THE STATE...WITH
AN UPPER LEVEL LOW OVER HUDSON BAY AND A WARM WESTERN RIDGE OVER THE
WEST COAST AND ROCKIES. WARM AND DRY AIR WAS SOUTHWEST OF THE UPPER
LEVEL JET WITH COOLER AIR TO THE NORTHEAST.
EARLY THIS MORNING ISOLATED SHOWERS DEVELOPED...LIKELY ALONG A
BOUNDARY BETWEEN A SOUTHERLY LOW LEVEL JET ALONG WESTERN NEBRASKA
INTO THE WESTERN DAKOTAS. ENOUGH LIFT WAS OCCURRING IN A NORTHWEST-
TO-SOUTHEAST FASHION ACROSS CENTRAL NORTH DAKOTA. THE LATEST
ITERATION OF THE HRRR INDICATES THE AREA OF ISOLATED SHOWERS
SHIFTING EAST TO THE JAMES VALLEY BEFORE SUNRISE...THEN CONTINUING
EAST OUT OF THE JAMES VALLEY.
A COLD FRONT OVER THE CENTRAL CANADIAN PRAIRIE PROVINCES THIS
MORNING IS FORECAST TO MOVE SOUTH TODAY AND ENTER NORTHWESTERN NORTH
DAKOTA BY THIS EVENING...SWEEPING SOUTHEAST ACROSS THE STATE
TONIGHT. LOOK FOR A VERY WARM DAY TODAY AHEAD OF THE FRONT. WESTERLY
MIXING WINDS ALOFT SHOULD INCREASE WITH THE APPROACH OF THE FRONT
DUE TO THE INCREASING PRESSURE GRADIENT. FORECAST SOUNDINGS INDICATE
AN ADIABATIC LINK FROM THE SURFACE UP TO AROUND H700 THIS AFTERNOON.
WENT ABOVE GUIDANCE FOR MAX TEMPS AND RAISED WINDS A BIT AS WELL
FROM GUIDANCE. LOOKING AT HIGHS TODAY IN THE LOW TO MID 90S OVER
MOST OF WESTERN AND CENTRAL NORTH DAKOTA.
TONIGHT AS THE COLD FRONT SWEEPS SOUTHEAST ACROSS THE STATE...THE
BEST UPPER LEVEL FORCING RESIDES TO OUR NORTHEAST IN THE FLOW OF THE
UPPER JET - WHICH SHOULD HAVE LIFTED NORTHEAST DURING THE DAY
ALLOWING THE VERY WARM AND DRY AIR TO ADVANCE INTO CENTRAL NORTH
DAKOTA. HAVE KEPT THE SLIGHT CHANCES OF THUNDERSTORMS ACROSS THE
TURTLE MOUNTAIN AREA. COOLER AIR MOVES INTO THE STATE TONIGHT WITH
NORTHWEST WINDS BEHIND THE COLD FRONT. KEPT LOWS TONIGHT IN THE 50S
AS THE NORTHWEST WINDS WILL KEEP THE LOWER ATMOSPHERE MIXED ENOUGH
SO THAT TEMPS DO NOT DROP INTO THE 40S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 301 AM CDT SAT AUG 1 2015
COOLER TEMPERATURES EXPECTED OVER THE AREA ON SUNDAY IN THE WAKE
OF THE COLD FRONT. OTHERWISE...DRY CONDITIONS EXPECTED WITH UPPER
RIDGE AXIS SLIDING OVER THE ROCKIES AND SURFACE HIGH SETTLING OVER
THE REGION. DRY WEATHER CONTINUES INTO MONDAY WITH RIDGE AXIS
PUSHING TOWARDS THE NORTHERN PLAINS.
ACTIVE WEATHER PATTERN EXPECTED TOWARDS MID-WEEK WITH RIDGE
BREAKING DOWN AND A VARIETY OF SHORT WAVES EJECTING OVER THE AREA
FROM A BROAD UPPER LOW OVER BRITISH COLUMBIA. UNSETTLED PATTERN
CONTINUES INTO THE END OF THE WEEK AS LOW STARTS TO MAKE ITS WAY
EASTERLY. BELOW AVERAGE TEMPERATURES EXPECTED THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1223 AM CDT SAT AUG 1 2015
VFR CONDITIONS WILL CONTINUE THROUGH THE FORECAST PERIOD. SURFACE
FLOW WILL REMAIN LIGHT AND VARIABLE FOR THE NIGHTTIME HOURS. ON
SATURDAY WINDS SHOULD BECOME SOUTHERLY OR SOUTHWESTERLY AHEAD OF
A COLD FRONT THAT IS FORECAST TO MOVE THROUGH KISN AROUND 00Z...AND
THROUGH KMOT AND KDIK AROUND 04Z SATURDAY EVENING. SOUTHWEST WINDS
COULD BE GUSTY AT TIMES AT KISN AND KDIK IN THE AFTERNOON BETWEEN
17Z AND 00Z.
&&
.FIRE WEATHER...
ISSUED AT 301 AM CDT SAT AUG 1 2015
AN ADIABATIC LAPSE RATE UP TO H700 THIS AFTERNOON WILL ALLOW
MIXING WINDS ALOFT TO LINK WITH THE SURFACE. EXPECTING 15 TO 20
MPH WINDS FOR A TIME THIS AFTERNOON IN THE WEST AS TEMPERATURES
REACH INTO THE 90S. DEWPOINTS IN THE 40S OVER SOUTHWESTERN NORTH
DAKOTA THIS MORNING ARE EXPECTED TO DROP INTO THE 30S THIS
AFTERNOON AS THE LOWER ATMOSPHERE MIXES WITH MID LEVELS.
TEMPERATURES IN THE MID 90S WITH DEWPOINTS IN THE 30S SHOULD
RESULT IN MINIMUM RELATIVE HUMIDITY VALUES IN THE 10 TO 15 PERCENT
RANGE OVER MUCH OF WESTERN NORTH DAKOTA...MAINLY ALONG AND WEST OF
A LINE FROM WILLISTON TO WATFORD CITY TO DICKINSON AND HETTINGER.
IN ADDITION...WINDS ALOFT SHOULD ALSO MIX DOWN TO THE SURFACE FOR
A TIME THIS AFTERNOON...WITH WESTERLY WINDS OF 15 TO 20 MPH
EXPECTED.
EXPECT THAT GRASSLANDS IN THE SOUTHWEST ARE CURING QUICKLY.
THE LATEST ASSESSMENT FROM LAND MANAGERS INDICATED THAT SLOPE AND
BOWMAN COUNTIES WOULD LIKELY BE THE FIRST TO REACH CRITICAL FUEL
MOISTURE LEVELS AT SOME POINT. WEATHER CONDITIONS EXPECTED TODAY
WOULD WARRANT A RED FLAG MENTION FOR WILLISTON TO HETTINGER AND
WESTWARD...BUT UNDERSTAND THAT GRASSLANDS HAVE NOT YET REACHED
CRITICAL FUEL MOISTURE LEVELS.
COOLER CONDITIONS WITH HIGHER RELATIVE HUMIDITY VALUES ARE EXPECTED
ON SUNDAY...AFTER A COLD FRONTAL PASSAGE SATURDAY NIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...JV
LONG TERM...JJS
AVIATION...JV
FIRE WEATHER...JV
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
300 AM CDT SAT AUG 1 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM CDT SAT AUG 1 2015
AS NORTHWEST UPPER FLOW CONTINUES...MAIN CHALLENGE IN SHORT TERM IS
EXTENT OF CONVECTION TONIGHT...INCLUDING TRACK OF ANY CONVECTIVE
SYSTEMS AND OVERALL STRENGTH. AREA REMAINS BETWEEN FASTER NORTHWEST
FLOW TO THE NORTH AND HIGHER INSTABILITY TO THE SOUTHWEST BUT THIS
BORDER AREA WILL COME INTO PLAY NEXT 24 HOURS IT APPEARS.
RELATIVELY SMALL AREA OF HIGHER THETA-E AND RELATED PRECIPITABLE
WATER VALUES ACROSS SOUTHEAST MINNESOTA EARLY THIS MORNING...
COMBINED WITH SOME CONVERGENCE...HAS LED TO DEVELOPMENT OF MID LAYER
CLOUDS AND WIDELY SCATTERED CONVECTION EARLY THIS MORNING BETWEEN
KLSE AND KMSP. COVERAGE SHOULD REMAIN MINOR AS CELLS MOVE SOUTHEAST
IN MID LEVEL FLOW...BUT HAVE INTRODUCED SCATTERED ACTIVITY INTO THE
DAYBREAK HOURS.
WHILE MOST OF THE DAY WILL REMAIN QUIET...FOCUS SHIFTS ON TONIGHT.
SHORT WAVE MOVING OUT OF MONTANA THIS MORNING WILL DRIFT SOUTHEAST
INTO THE CORNBELT REGION TODAY. RESPONSE TO THIS WILL BE IN THE FORM
OF STRENGTHENING LOW LEVEL JET AND MOISTURE TRANSPORT THIS EVENING
TO THE SOUTHWEST...WHICH WILL LEAD TO MORE DEFINED WARM FRONT.
WHILE STORM DEVELOPMENT IS EXPECTED TO THE WEST AND SOUTHWEST
INITIALLY...QUESTIONS ABOUND ON WHERE THAT CONVECTION WILL TRACK
GIVEN FLOW AND WARM FRONT LOCATION. INITIAL ACTIVITY COULD DIVE
SOUTHEAST AND MISS MOST OF AREA...FAVORING HIGHER MIXED LAYER CAPE
VALUES TO THE SOUTHWEST...AS MODELS CONTINUE TO OVERDUE EXTENT OF
NORTHEAST PUSH OF HIGHER SURFACE DEW POINTS. 01.00Z NAM CERTAINLY
FAVORS THIS SOLUTION. AND IF THAT HAPPENS...HOW MUCH CONVECTION
WOULD FIRE NORTH OF THERE IS BIG QUESTION AS SOME MESOSCALE MODELS
ADVERTISE.
PATH OF MCS WILL BE KEY THIS EVENING...ESPECIALLY NEAR WARM FRONT
GIVEN EXPECTED HIGHER LOW LEVEL SHEAR. WILL CONTINUE TO HONOR DAY 1
SLIGHT RISK BY STORM PREDICTION CENTER BUT KEEP PRODUCT SUITE IN
CONDITIONAL...LOW CONFIDENCE MODE UNTIL STORM TRACK AND BOUNDARY
LOCATION CAN BE BETTER DETERMINED. STORMS COULD BEGIN TO IMPACT
WESTERN AREAS AROUND MID EVENING /02.02Z/ AND THEN MIGRATE THROUGH
OVERNIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 300 AM CDT SAT AUG 1 2015
SUNDAY SETUP WILL AT LEAST PARTIALLY BE DETERMINED BY HOW TONIGHT
PLAYS OUT. STRONGER SHORT WAVE TROUGH IN NORTHWEST FLOW WILL DIVE
INTO WESTERN GREAT LAKES BY LATE SUNDAY AND DEPENDING ON WHERE
BOUNDARY IS LINGERING...COULD SEE REDEVELOPMENT. APPEARS BEST LOW
LEVEL RESPONSE TO WORK ON FRONT WILL PUSH INTO SOUTHERN WISCONSIN
AND NEIGHBORING AREAS. WE COULD SEE SOME INITIAL DEVELOPMENT IN
EASTERN AND SOUTHERN AREAS BEFORE CONVECTION QUICKLY MOVES OFF... OR
ACTIVITY COULD EVEN FLARE UP JUST SOUTHEAST OF AREA WHERE HIGHER
INSTABILITY LEVELS LIKELY TO BE ESTABLISHED.
RAIN THREAT QUICKLY EXITS SUNDAY EVENING AS A MORE QUIET NORTHWEST
REGIME FLOW RETURNS FOR EARLY PART OF WEEK. COOLER TEMPERATURES LOOK
ON TRACK BEHIND SUNDAYS WAVE AS WELL.
BY MID WEEK...MORE SHORT WAVE TROUGHS CROSSING FLATTENING UPPER
RIDGE TO THE WEST WILL BRING RAIN THREATS BACK INTO AREA. COOLER AND
DRIER FLOW WOULD LIKELY LIMIT ANY SEVERE WEATHER POTENTIAL WITH THAT
ACTIVITY BUT WILL HAVE TO WAIT AND SEE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1145 PM CDT FRI JUL 31 2015
CONFIDENCE ON ANY SHOWERS DEVELOPING OVERNIGHT REMAINS PRETTY LOW
BUT STARTING TO SEE SOME CLOUDS FORMING OVER CENTRAL MINNESOTA.
THE RUNS OF THE HRRR THROUGH THE EVENING WERE INITIALLY DRY BUT
NOW ARE SHOWING SOME ACTIVITY AS WELL. WILL LEAVE IN THE VCSH FOR
BOTH TAF SITES BUT NOT EXPECTING ANY SHOWERS THAT DO DEVELOP TO
AMOUNT TO A WHOLE LOT. CLEAR SKIES EXPECTED FOR SATURDAY AS THE
SURFACE HIGH MOVES ACROSS THE REGION. THE 01.00Z NAM SUGGESTS THAT
CONVECTION SHOULD FORM AHEAD OF THE NEXT SYSTEM OVER SOUTHEAST
SOUTH DAKOTA SATURDAY AFTERNOON ON THE NOSE OF THE DEVELOPING LOW
LEVEL JET. THIS ACTIVITY SHOULD THEN MOVE SOUTHEAST INTO THE CAPE
POOL AND HOW MUCH MOISTURE RETURN THERE WILL BE BACK INTO THE AREA
IS VERY QUESTIONABLE. THE NAM FORECAST SOUNDINGS ARE VERY DRY IN
THE MID AND LOW LEVELS SO HAVE ONLY BROUGHT IN SOME SCATTERED MID
LEVEL CLOUDS WITH A WIND SHIFT TO THE SOUTH.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...SHEA
LONG TERM...SHEA
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1145 PM CDT FRI JUL 31 2015
.SHORT TERM...(TONIGHT THRU SATURDAY NIGHT)
ISSUED AT 315 PM CDT FRI JUL 31 2015
MAIN FCST CONCERNS THIS PERIOD...SMALL SHRA/ISOLATED TSRA CHANCES
LATE TONIGHT...SHRA/TSRA CHANCES/SEVERE THREAT SAT NIGHT.
18Z DATA ANALYSIS HAD STRONG LOW PRESSURE OVER HUDSONS BAY AND BROAD
HIGH PRESSURE OVER THE CENTRAL/NORTHERN PLAINS INTO THE MID MS
VALLEY. PRESSURE GRADIENT BETWEEN THE TWO REMAINED OVER WI/MN/
EASTERN IA. DIURNAL WARMING AND MIXING TO 5K FT ONCE AGAIN PRODUCING
BRISK/GUSTY NORTHWEST WINDS ACROSS MUCH OF THE REGION. MOISTURE
CLOSER TO THE LOW AND COOLER MID LEVEL TEMPS ALLOWING FOR DIURNAL
CUMULUS ALONG/NORTHEAST OF I-94. GENERALLY CLEAR SKIES ELSEWHERE.
EARLY AFTERNOON TEMPS NEAR NORMAL FOR THE LAST DAY OF JULY.
31.12Z MODEL RUNS LOOK TO HAVE INITIALIZED QUITE WELL THIS MORNING.
SOLUTIONS VERY SIMILAR AS ONE STRONGER SHORTWAVE DROPS INTO THE
EASTERN GREAT LAKES TONIGHT...WEAK SHORTWAVE RIDGING SLIDES ACROSS
THE REGION SAT THEN AS HGTS FALL SAT NIGHT AHEAD OF A STRONGER
SHORTWAVE ENERGY DROPPING SOUTH ACROSS MANITOBA AND COMING THRU THE
WESTERN NOAM RIDGING. TREND IS STRONGER WITH THE HGT FALLS/
SHORTWAVE ENERGY DROPPING TOWARD/INTO THE REGION SAT NIGHT. GIVEN
THE TIGHT MODEL CONSENSUS...SHORT-TERM FCST CONFIDENCE IS GOOD THIS
CYCLE.
WEAK SHORTWAVE OVER MT THIS AFTERNOON SLIDES QUICKLY EAST-SOUTHEAST
TONIGHT...BRINGING WITH IT A ROUND OF 850-700MB WARM ADVECTION AND
MOISTURE TRANSPORT. THIS WITH WEAK CAPE WHEN LIFTING PARCELS IN THE
850-700MB LAYER. RATHER CONSISTENT SIGNAL AMONG HIGH-RES/WRF MODELS
FOR THIS WEAK WAVE AND LOWER LEVEL THERMO-DYNAMIC FORCING TO PRODUCE
SOME ISOLATED TO SCT SHRA ACROSS THE AREA LATER TONIGHT...MAINLY
BETWEEN 06-12Z. ADDED A 20 PERCENT SHRA/ISOLATED TSRA MENTION TO
THIS PERIOD TONIGHT...MAINLY SOUTHWEST OF I-94. QUIET/DRY SAT AS
HGTS RISE A BIT AND A WEAK SFC RIDGE AXIS DRIFTS EAST ACROSS THE
UPPER MIDWEST. SFC/LOW LEVEL FLOW FINALLY SWINGS MORE WEST/SOUTHWEST
WITH LOWER LEVEL WARM ADVECTION SPREADING ACROSS THE AREA. SOME
INCREASE OF 700MB MOISTURE/CLOUDS LOOK TO OFFSET THE 925MB
WARMING...WITH HIGHS SAT SIMILAR TO THOSE OF THE PAST FEW DAYS.
MOISTURE CONTINUES TO INCREASE SAT NIGHT...AHEAD OF THE LOWER LEVEL
TROUGH AND THE FALLING HGTS ALOFT. MODEL SOUNDINGS SHOWING THE BULK
OF THE MOISTURE/SATURATION AND RESULTING MUCAPE IS ABOVE 850MB...
WITH ANYWHERE FROM 100-500 CIN/CAPPING INDICATED FOR THE SFC-925MB
LAYER SAT NIGHT. MAJORITY OF THE FORCING/LIFT WITH THE SHORTWAVE
DROPPING TOWARD THE REGION IS OVER NORTHERN MN/NORTHERN WI WHILE
HIGHER OF THE CAPE IS OVER IA/NEARBY AREAS. PER MODEL SOUNDINGS...PW
VALUES ARE IN THE 0.75 TO 1.3 INCH RANGE SAT NIGHT. LEFT SHRA/TSRA
CHANCES SAT NIGHT IN THE 20-50 PERCENT RANGE BUT DID ADD SOME
TEMPORAL RESOLUTION BRINGING THESE CHANCES SOUTHEAST ACROSS THE
AREA. CONFIDENCE NOT HIGH ON ANY SEVERE THREAT WITH TSRA SAT NIGHT.
THIS GIVEN THE ELEVATED NATURE OF THE MOISTURE/INSTABILITY...STRONG
BOUNDARY LAYER CAPPING AND BULK SHEAR WHEN LIFTING 850-700MB PARCELS
LOOKING TO BE AROUND 20 KTS. SEE SWODY2 FOR MORE DETAILS. USED A
BLEND OF THE GUIDANCE LOWS/HIGHS FOR TONIGHT THRU SAT NIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 315 PM CDT FRI JUL 31 2015
MAIN FCST CONCERNS FOR SUNDAY THRU MONDAY NIGHT...SHRA/TSRA CHANCES
SUN/SUN NIGHT...TEMPERATURES THRU THE PERIOD.
31.12Z MODELS IN GOOD AGREEMENT FOR THE TROUGH/SHORTWAVE ENERGY TO
DROP INTO/ACROSS THE REGION SUN/SUN NIGHT. TREND CONTINUES ON THE
STRONGER SIDE WITH THIS WAVE/ENERGY AS IT PASSES. MODELS IN DECENT
AGREEMENT FOR SLOW EASTWARD PROGRESSION OF THE LONGWAVE LOW/TROUGH
AND WESTERN NOAM RIDGING MON/MON NIGHT. IMPROVING SIGNAL FOR SOME
STRONGER SHORTWAVE ENERGY TO MOVE EAST THRU THE RIDGING...REACHING
THE CENTRAL PLAINS BY 12Z TUE BUT REMAINING WELL WEST/SOUTH OF THE
FCST AREA. FCST CONFIDENCE IN THE SUN THRU MON NIGHT PERIOD IS
GENERALLY GOOD THIS CYCLE.
FCST AREA REMAINS AHEAD OF THE SFC-925MB TROUGH/FRONT SUN.
TIGHTENING CONSENSUS FOR THIS BOUNDARY TO MOVE SOUTHEAST ACROSS THE
AREA SUN...REACHING A KGRB-KDBQ-KDSM LINE AROUND 00Z MON. FORCING
ALONG THIS TROUGH/FRONT APPEARS TO BE RATHER WEAK...WITH THE MAIN
SHORTWAVE ENERGY PASSING NORTH/EAST OF THE FCST AREA. MODEL
SOUNDINGS SHOWING CONSIDERABLE CAPPING WITH AN INVERSION BETWEEN 900-
850MB THRU MUCH OF THE DAY. FRONT MAY PASS THRU MUCH OF THE FCST
AREA BEFORE THE CAPPING ERODES ENOUGH TO ALLOW FOR CONVECTION. LEFT
SOME SMALL SHRA/TSRA CHANCES IN THE SOUTHEAST END OF THE FCST AREA
SUN MORNING...FOR POTENTIAL OF LINGERING/SLOWING SHRA/TSRA FROM SAT
NIGHT. CARRIED A 20-30 PERCENT SHRA/TSRA CHANCE FOR MUCH OF THE AREA
SUN AFTERNOON GIVEN THE UNCERTAINTIES AND THE FRONT IN THE AREA.
LEFT SOME 20-30 PERCENT SHRA/TSRA CHANCES MAINLY SUN EVENING AND
MAINLY TO BLEND WITH NEIGHBORING GRIDS. HOWEVER...PASSAGE OF THE SFC-
850MB TROUGH/FRONT NOW LOOKS TO TAKE THE SHRA/TSRA CHANCES WITH IT
WHICH WOULD LEAVE MUCH OF THE FCST AREA DRY SUN NIGHT. WEAK HIGH
PRESSURE AND DRYING SPREAD IN FOR MON/MON NIGHT. SOME WEAK LOWER
LEVEL MOISTURE TRANSPORT/ISENTROPIC LIFT ASSOCIATED WITH THE
SHORTWAVE ENERGY COMING ACROSS THE CENTRAL PLAINS GRAZES THE
SOUTHWEST END OF THE FCST AREA LATER MON NIGHT. INCLUDED A SMALL
SHRA/TSRA CHANCE ACROSS THE FAR SOUTHWEST END OF THE FCST AREA TO
BLEND WITH THE NEIGHBORING GRIDS. WARM AIRMASS OVER THE AREA SUNDAY
AHEAD OF THE FRONT WITH MDT LOW LEVEL COLD ADVECTION SPREADING OVER
THE AREA SUN NIGHT INTO MON BEHIND THE FRONT. MODEL/ENSEMBLE
CONSENSUS OF ABOVE NORMAL HIGHS IN THE LOW-MID 80S ON SUNDAY LOOKS
GOOD. STAYED WITH THE CONSENSUS BLEND OF LOWS/HIGHS FOR SUN NIGHT
THRU MON NIGHT.
FOR TUESDAY THRU FRIDAY...DAYS 4 TO 7...
MAIN FCST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES FOR TUE NIGHT AND
BEYOND...TEMPERATURES.
MEDIUM RANGE MODELS OF 31.00Z/31.12Z IN REASONABLY GOOD AGREEMENT
FOR THE UPPER MIDWEST TO REMAIN UNDER NORTHWEST FLOW ALOFT THRU NEXT
WEEK. THIS AS A MID LEVEL LOW OVER JAMES BAY ON TUE DRIFTS VERY
SLOWLY EAST INTO QUEBEC BY FRI AND RIDGING OVER THE ROCKIES ON TUE
ONLY MOVES TO CENTRAL NOAM BY FRI. OVERALL TREND FAVORS A TIGHTENING
CONSENSUS OF THE EARLIER RUNS. FCST CONFIDENCE FOR TUE THRU FRI IS
AVERAGE THIS CYCLE.
EVEN WITH A RATHER GOOD CONSENSUS AMONG THE MODELS WITH THE LONGWAVE
PATTERN OVER NOAM TUE-FRI...PLENTY OF DETAIL DIFFERENCES WITH
SHORTWAVE DETAILS IN THE FLOW. SHORTWAVE ENERGY CROSSING THE PLAINS
STAYS WEST OF THE AREA TUE...WITH SOME CONSENSUS FOR SOME PORTION OF
THIS ENERGY TO PUSH ACROSS THE REGION WED. SOME SIGNAL FOR ANOTHER
WAVE TO COME THRU THE RIDGING AND MOVE ACROSS THE REGION THU...THEN
A MORE NORTHERN STREAM WAVE TO DROP SOUTH OUT OF CAN INTO THE UPPER
MIDWEST FRI. WILL LEAVE TUE DRY WITH HIGH PRESSURE...A DRIER AIRMASS
AND LACK OF SHORTWAVE ENERGY MOVING ACROSS THE AREA. MOISTURE STARTS
TO INCREASE TUE NIGHT/WED...WITH A WAVE OF LOW PRESSURE AND THE
SHORTWAVE ENERGY WORKING EAST ACROSS THE CENTRAL/NORTHERN PLAINS.
MORE/DEEPER MOISTURE THEN PROGGED OVER THE AREA FOR WED NIGHT INTO
FRI...AS OTHER SHORTWAVES WOULD RIPPLES ACROSS THE REGION. CONSENSUS
SHRA/TSRA CHANCES IN THE 20-40 PERCENT RANGE FOR WED THRU FRI OKAY
FOR NOW UNTIL THE DETAILS SORT THEMSELVES OUT. WITH THE CONTINUED
NORTHWEST FLOW ALOFT...MODEL CONSENSUS TEMPERATURES A CATEGORY OR
TWO BELOW NORMAL FOR TUE-FRI APPEAR REASONABLE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1145 PM CDT FRI JUL 31 2015
CONFIDENCE ON ANY SHOWERS DEVELOPING OVERNIGHT REMAINS PRETTY LOW
BUT STARTING TO SEE SOME CLOUDS FORMING OVER CENTRAL MINNESOTA.
THE RUNS OF THE HRRR THROUGH THE EVENING WERE INITIALLY DRY BUT
NOW ARE SHOWING SOME ACTIVITY AS WELL. WILL LEAVE IN THE VCSH FOR
BOTH TAF SITES BUT NOT EXPECTING ANY SHOWERS THAT DO DEVELOP TO
AMOUNT TO A WHOLE LOT. CLEAR SKIES EXPECTED FOR SATURDAY AS THE
SURFACE HIGH MOVES ACROSS THE REGION. THE 01.00Z NAM SUGGESTS THAT
CONVECTION SHOULD FORM AHEAD OF THE NEXT SYSTEM OVER SOUTHEAST
SOUTH DAKOTA SATURDAY AFTERNOON ON THE NOSE OF THE DEVELOPING LOW
LEVEL JET. THIS ACTIVITY SHOULD THEN MOVE SOUTHEAST INTO THE CAPE
POOL AND HOW MUCH MOISTURE RETURN THERE WILL BE BACK INTO THE AREA
IS VERY QUESTIONABLE. THE NAM FORECAST SOUNDINGS ARE VERY DRY IN
THE MID AND LOW LEVELS SO HAVE ONLY BROUGHT IN SOME SCATTERED MID
LEVEL CLOUDS WITH A WIND SHIFT TO THE SOUTH.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...04
AREA FORECAST DISCUSSION
NWS TUCSON AZ
335 AM MST SAT AUG 1 2015
.SYNOPSIS...ENOUGH MOISTURE WILL LINGER TODAY TO BRING A CHANCE OF
MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS TO MUCH OF
SOUTHEAST ARIZONA. THEREAFTER A DRYING TREND WILL OCCUR WHICH WILL
RESULT IN MORE ISOLATED SHOWER AND THUNDERSTORM ACTIVITY CONFINED
MAINLY TO AREAS SOUTH AND EAST OF TUCSON.
&&
.DISCUSSION...IR SATELLITE LOOPS SHOW GRADUALLY CLEARING SKIES
ACROSS SOUTHERN PORTIONS OF THE CWA...WITH MOSTLY CLOUDY CONDITIONS
ELSEWHERE AS OVERNIGHT CONVECTIVE DEBRIS CONTINUES TO THIN. SURFACE
OBSERVATIONS FROM AROUND THE REGION EARLY THIS MORNING SHOW
DEWPOINTS GENERALLY IN THE LOW TO MID 60S F...MORE OR LESS UNCHANGED
FROM 24 HOURS AGO (PERHAPS A SHADE DRIER)...WITH AN IMPRESSIVE 71 F
DEWPOINT AT KPHX THANKS IN PART TO EARLIER SHOWERS AND STORMS. THE
CIRA PRECIPITABLE WATER PRODUCT SHOWS THAT WE`RE STILL QUITE MOIST
THROUGH THE ATMOSPHERIC COLUMN...WITH PW VALUES OF AROUND 1.3-1.4
INCHES NEAR TUCSON AND A TOUCH HIGHER TO THE WEST.
ALOFT...LATEST ANALYSES REVEAL A PRETTY CHAOTIC UPPER-AIR
PATTERN...WITH SEVERAL HIGH PRESSURE CENTERS STRUNG OUT ACROSS THE
GREAT BASIN AND SOUTHEASTWARD INTO THE TRANS-PECOS REGION OF TEXAS.
WATER VAPOR LOOPS IMPLY A LOCAL ENHANCEMENT TO THE UPPER-LEVEL FLOW
PUNCHING INTO CENTRAL PORTIONS OF THE BAJA PENINSULA AND GULF OF
CALIFORNIA...WHICH IS BACKED-UP BY THE LATEST RAP ANALYSIS. THE NOSE
OF THIS SUBTLE JET STREAK MAY PLAY A ROLE IN INITIATING CONVECTION
LATER TODAY ACROSS CENTRAL AND POSSIBLY WESTERN PORTIONS OF THE CWA.
SOME ISSUES TO CONTEND WITH FOR TODAY`S FORECAST REVOLVE AROUND
SLIGHTLY WARMER MID-LEVEL TEMPERATURES...POSSIBLE ISSUES WITH ANVIL
SHADING OWING TO A SOUTH TO SOUTHEASTERLY STEERING FLOW...AND THE
WIDE VARIETY OF SOLUTIONS OFFERED UP BY VARIOUS CONVECTIVE ALLOWING
MODELS. HOWEVER...BOTH THE 05Z RUN OF THE HRRRX (EXPERIMENTAL HRRR)
AND THE 00Z UNIV. OF AZ WRF-NAM SOLUTIONS PAINT A FAIRLY SIMILAR
PICTURE FOR TODAY...WITH THE MAIN CONVECTIVE FOCUS ACROSS PARTS OF
PINAL...PIMA...AND SANTA CRUZ COUNTIES AND GENERALLY MORE ISOLATED
COVERAGE OUT EAST. THESE SOLUTIONS GENERALLY LINE UP WITH THE RECENT
RUNS OF THE NAM/GFS WHICH SHOW THE BEST INSTABILITY LINING UP FROM
TUCSON AND POINTS WEST...EFFECTIVELY WITHIN THE ZONE OF HIGHER PW
AIR AS MENTIONED EARLIER.
FOR SUNDAY AND BEYOND...THE GENERAL PATTERN IS FORECAST TO BEGIN A
RE-ORGANIZATION PHASE AS THE UPPER-HIGH RECONSOLIDATES...EVENTUALLY
NEAR THE FOUR-CORNERS REGION BY THE MIDDLE TO END OF NEXT WEEK. IN
THE MEAN TIME...SOUTHWESTERLY OR WESTERLY MID-LEVEL FLOW WILL USHER
DRIER AIR INTO THE AREA WHICH WILL RESULT IN MARKEDLY REDUCED
PRECIPITATION CHANCES...PARTICULARLY BY TUESDAY. THEREAFTER...MORE
FAVORABLE SOUTHEASTERLY FLOW SHOULD ONCE AGAIN BEGIN TO PUMP
MOISTURE...AND AS A RESULT SOMEWHAT BETTER SHOWER AND STORM
COVERAGE...BACK INTO THE REGION. THE ROLLER COASTER RIDE THAT IS THE
MONSOON 2015 CONTINUES...
&&
.AVIATION...VALID THRU 02/12Z.
DECREASING CLOUD COVER THIS MORNING. SCT TO BKN CLOUDS 7-10K FT AGL
RE-DEVELOPING DURING THE LATE-MORNING ALONG WITH ISOLD-SCT SHRA/TSRA
DEVELOPING AFTER 01/19Z. THE GREATEST COVERAGE TODAY LOOKS TO OCCUR
NEAR THE KTUS AND KOLS TERMINALS AND NEAR THE HIGH TERRAIN NORTHEAST
OF KSAD. BRIEF MVFR CONDITIONS WITH ERRATIC WIND GUSTS TO 40 KTS
POSSIBLE IN AND AROUND THE STRONGER TSRA. OUTSIDE OF STORM
INFLUENCES SFC WINDS WILL GENERALLY BE LESS THAN 12 KTS WITH A FEW
HIGHER GUSTS IN THE AFTERNOON/EARLY EVENING HOURS. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...ENOUGH MOISTURE WILL LINGER TODAY FOR A CHANCE OF
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WITH THE GREATEST
COVERAGE FROM NEAR TUCSON AND POINTS WEST. THEN...MORE SOUTHWESTERLY
WINDS ALOFT ON SUNDAY WILL BRING DRIER AIR INTO THE REGION FOR
ISOLATED TO SCATTERED THUNDERSTORM COVERAGE TO BEGIN NEXT
WEEK...WITH A FOCUS MAINLY SOUTH AND EAST OF TUCSON. OUTSIDE OF
THUNDERSTORM WIND GUSTS...20-FT WINDS WILL GENERALLY BE TERRAIN
DRIVEN AND LESS THAN 15 MPH. HOWEVER SOME AFTERNOON AND EARLY
EVENING BREEZINESS IS LIKELY DUE TO DAYTIME HEATING...ESPECIALLY
THROUGH THE GILA VALLEY NEAR SAFFORD.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
CARLAW
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS ALBANY NY
943 AM EDT SAT AUG 1 2015
.SYNOPSIS...
A WEAK COLD FRONT AND AN UPPER LEVEL DISTURBANCE WILL
BRING ISOLATED TO SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS TO
EASTERN NEW YORK AND WESTERN NEW ENGLAND TODAY. HIGH PRESSURE WILL
BRIEFLY BUILD IN FROM THE TENNESSEE VALLEY AND THE MID ATLANTIC
STATES TONIGHT INTO SUNDAY WITH FAIR AND DRY WEATHER. A STRONGER
COLD FRONT WILL BRING MORE SCATTERED SHOWERS AND THUNDERSTORMS FOR
MONDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 943 AM EDT...UPSTATE NEW YORK AND NEW ENGLAND WILL BE UNDER
THE INFLUENCE OF CYCLONIC FLOW ALOFT TODAY. THE FIRST PUSH OF
POSITIVE VORTICITY ADVECTION HAS MOVED THROUGH THE REGION EARLIER
THIS MORNING WITH A ROUND OF LIGHT RAIN SHOWERS. THESE RAIN
SHOWERS HAVE NOW PUSHED INTO NEW ENGLAND...LEAVING DRY CONDITIONS
OVER THE CWA FOR THE TIME BEING. MODEL GUIDANCE...INCLUDING THE
3KM HRRR...SHOWS THAT SOME MORE CELLULAR ACTIVITY MAY DEVELOP
DURING PEAK HEATING LATER TODAY.
THE STEEPEST MID LEVEL LAPSE RATES WILL GENERALLY BE NORTH OF THE
MOHAWK VALLEY/CAPITAL REGION IN THE 6.5-6.8 C/KM RANGE. H500
TEMPS WILL FALL CLOSE TO -14C TO -16C FROM THE CAPITAL DISTRICT
NORTH. THE INSTABILITY CONTINUES TO BE THE BIGGEST QUESTION TODAY
FOR ANY SUSTAINED CONVECTION...WITH THE NAM STILL PAINTING SBCAPE
VALUES OF 500-1000 J/KG WITH SOME GREATER POCKETS...WHILE THE GFS
IS IN THE 100-500 J/KG RANGE WITH THE GREATER SBCAPES NORTH. 0-6
KM BULK SHEAR VALUES ARE IN THE 30-45 KT RANGE...BUT THE BETTER
SHEAR IS OUT OF PHASE WITH THE BETTER INSTABILITY. THE BETTER
SHEAR IS SOUTH OF THE CAPITAL REGION. SFC DEWPTS WILL GENERALLY BE
IN THE 50S WITH SPOTTY 60F READINGS. IT APPEARS A FEW MULTI-
CELLS/CELLULAR CONVECTION IS POSSIBLE...BUT FOR ANY STRONG TALLER
UPDRAFTS...MORE INSTABILITY WOULD NEED TO BE UTILIZED. CAN NOT
RULE OUT A ROGUE/ISOLD SEVERE CELL TO THE NORTH...BUT ANY
CONVECTION WITH THE COLD POOL/STEEPER LAPSE RATES MAY YIELD PEA TO
PERHAPS DIME/PENNY SIZE HAIL. THE MARGINAL RISK FURTHER DOWNSTREAM
OUTSIDE OF THE ALY FCST AREA ACROSS NRN NEW ENGLAND LOOKS ON TRACK
FROM SPC.
AS SEEN IN THE LATEST 3KM HRRR GUIDANCE...THE CHANCE FOR ISOLD
THUNDERSTORMS WILL INCREASE TOWARDS NOON AND INTO THE
AFTERNOON...BUT WILL DIMINISH TOWARDS SUNSET. THE WINDS WILL
INCREASE FROM THE WEST/SOUTHWEST AT 10 TO 20 MPH...WITH HIGH TEMPS
GETTING INTO THE U70S TO L80S IN THE VALLEY AREAS...EXCEPT FOR THE
MID HUDSON VALLEY/SRN LITCHFIELD CTY WHERE SOME MID/U80S ARE
POSSIBLE. U60S TO U70S WILL BE COMMON OVER THE HILLS AND MTNS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
TONIGHT...ANY LEFTOVER CELLULAR SHOWERS/THUNDERSTORMS SHOULD
QUICKLY DIMINISH BTWN 6-9 PM WITH THE LOSS OF THE DIURNAL
HEATING. THE ATMOSPHERE SHOULD STABILIZE...AND THE CLOUDS WILL
THIN. THERE MAYBE BE PATCHY FOG WHERE ANY RAIN OCCURS...AND ACROSS
PORTIONS OF THE LAKE GEORGE REGION...SRN VT...BERKSHIRES...NEAR
THE CT RIVER VALLEY...AND DOWN THE HUDSON RIVER VALLEY. THE
DECOUPLING WINDS AND CLEARING SKIES WILL ALSO PROMOTE SHALLOW
RADIATIONAL MIST OR FOG. LOWS WERE FAVORED WITH A BLEND OF THE
MAV/MET GUIDANCE WITH M50S TO AROUND 60F IN MOST
LOCATIONS...EXCEPT SOME U40S TO L50S IN THE SHELTERED VALLEY
LOCATIONS...AND ACROSS PARTS OF THE SRN DACKS...BERKS...NRN
TACONICS...AND SRN VT.
SUNDAY...THE SHORT-RANGE GUIDANCE IS IN AGREEMENT FOR A DRY CLOSE
TO THE WEEKEND WITH SFC HIGH PRESSURE BUILDING IN FROM THE
VIRGINIAS. THE MID AND UPPER LEVEL FLOW SHIFTS FROM ZONAL TO
SOUTHWESTERLY...AS THE NEXT UPPER LEVEL TROUGH WILL BE
APPROACHING. THE WEAK LOW AND MID LEVEL RIDGING WILL ALLOW H850
TEMPS TO RISE BACK TO +15C TO +17C. PARTLY TO MOSTLY SUNNY
CONDITIONS WITH DECENT BOUNDARY LAYER MIXING DUE TO THE SW FLOW
SHOULD ALLOW TEMPS TO RISE INTO THE LOWER TO M80S IN THE VALLEY
AREAS...AND MID 70S TO AROUND 80F OVER THE HILLS AND MTNS.
SUNDAY NIGHT...LOW PRESSURE WILL BE MOVING TOWARDS SW QUEBEC. A
COLD FRONT WILL BE MOVING THROUGH THE CNTRL-ERN GREAT LAKES
REGION. SOME SHORT-WAVE ENERGY WILL BE ROUNDING THE BASE OF THE
UPPER LEVEL TROUGH. CLOUDS WILL BE INCREASING FROM WEST TO EAST.
SLIGHT TO LOW CHC POPS WERE PLACED IN OVERNIGHT...ESPECIALLY NW/W
OF THE CAPITAL DISTRICT/HUDSON VALLEY. LOWS WILL BE MILDER THAN
THE PREVIOUS NIGHT WITH U50S TO M60S OVER THE REGION.
MONDAY-MONDAY NIGHT...INCLEMENT WEATHER RETURNS WITH THE COLD
FRONT MOVING ACROSS THE REGION POTENTIALLY DURING THE PEAK DIURNAL
HEATING. SOME STRONGER STORMS MAY BE POSSIBLE WITH INCREASING SFC
DEWPTS INTO THE 60S. SBCAPES MAY BE IN THE 500-1500 J/KG RANGE WITH
INCREASING BULK VERTICAL SHEAR AHEAD OF THE FRONT AND SHORT-WAVE.
DECENT HEIGHT FALLS SHOULD BE OCCURRING ALOFT WITH THE FRONT. THE
GFS HAS MID-LEVEL LAPSE RATES IN THE 6.5-7C/KM RANGE OVER THE FCST
AREA BY THE PM. THIS WILL HAVE TO BE MONITORED OVER THE NEXT FEW
DAYS FOR THE POSSIBILITY OF SOME SEVERE THUNDERSTORMS. SPC HAS
PLACED THE ENTIRE AREA IN A MARGINAL RISK FOR DAY 3.
SOME LOCALLY HVY DOWNPOURS WILL BE POSSIBLE TOO AS PWATS RISE
BACK TO THE 1.25-1.50 INCH RANGE. CHC AND LIKELY POPS HAVE BEEN
USED FOR MONDAY...AND TAPERED TO CHC POPS AT NIGHT. HIGHS WILL
RANGE FROM THE LOWER TO U80S IN THE VALLEY AREAS...AND M70S TO
L80S OVER THE HIGHER TERRAIN. LOWS MON NIGHT WILL BE IN THE M50S
TO M60S.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
A LARGE CLOSED OFF UPPER LEVEL LOW WILL BE THE DOMINATE FEATURE
NEXT WEEK. THE LOW IS EXPECTED MOVE EASTWARD ACROSS EASTERN CANADA
AS SHORT WAVES ROTATE ABOUT IT.GUIDANCE IS NOT IN AGREEMENT WITH
THE TIMING OF THE INDIVIDUAL SHORT WAVES AND THEIR INFLUENCE ON
THE LOW. HOWEVER THERE IS GENERAL AGREEMENT THE UPPER LEVEL FLOW
SHOULD BECOME MORE ZONAL BY LATE IN THE WEEK.
HAVE FAVORED GUIDANCE FROM THE WEATHER PREDICTION CENTER TO MAINTAIN
FORECAST CONSISTENCY WITH THE TIMING OF SYSTEMS. BASED ON THIS...A COLD
FRONT IS EXPECTED TO MOVE ACROSS THE AREA WEDNESDAY WITH THE BOUNDARY
EVENTUALLY STALLING NEAR THE MID ATLANTIC REGION AND OFF THE EAST COAST
FOR LATE IN THE WEEK. THERE ARE INDICATIONS A WAVE OF LOW PRESSURE SHOULD
MOVE ALONG THE BOUNDARY THURSDAY INTO FRIDAY. IN ADDITION...WITH COOL
TEMPERATURES ALOFT DIURNALLY DRIVEN SHOWERS WOULD BE EXPECTED HOWEVER
COVERAGE SHOULD BE FAIRLY ISOLATED. HAVE CHANCE POPS INTO THE SOUTHERN
PORTION F THE FORECAST AREA FOR THURSDAY OTHERWISE HAVE CLIMATOLOGICAL
SLIGHT CHANCE POPS IN THE FORECAST.
OVERALL EXPECTING SLIGHTLY BELOW NORMAL TEMPERATURES BY AROUND ABOUT
5 DEGREES. HIGHS MAINLY IN THE 70S (BIT COOLER ACROSS THE HIGHER TERRAIN)
WITH LOWS MAINLY IN THE 50S.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
A COUPLE OF PIECES OF ENERGY WILL MOVE THROUGH THE LONGWAVE TROUGH
OVER THE REGION TODAY. SOME LIGHT RAIN SHOWERS ARE CURRENTLY MOVING
ACROSS THE AREA THIS MORNING. A LULL IS THEN EXPECTED. THE NEXT WAVE
WILL HAVE THE HELP OF DAYTIME HEATING. ISOLATED TO SCATTERED STORMS
ARE EXPECTED FOR THE AFTERNOON HOURS. HAVE ADDRESSED THREAT WITH
VCSH SINCE DO NOT HAVE ENOUGH CONFIDENCE IN THE PLACEMENT AND TIMING
OF EXPECTED CONVECTION. STORMS WILL DISSIPATE WITH LOSS OF HEATING
AND PASSAGE OF THE WAVE.
MAINLY VFR CONDITIONS ARE EXPECTED. THE EXCEPTIONS ARE FOR MVFR
CONDITIONS WITH CONVECTION THIS AFTERNOON AND FOR MVFR FOG OVERNIGHT
AT KGFL AND KPSF.
LIGHT/VARIABLE TO CALM WINDS THROUGH THE EARLY MORNING WITH SOUTH TO
SOUTHWEST DEVELOPING AFTER SUNRISE. THE WINDS WILL SHIFT TO THE
SOUTHWEST TO WEST AS A WEAK COLD FRONTAL BOUNDARY MOVES ACROSS THE
REGION TODAY. THE WESTERLY FLOW IS EXPECTED TO BECOME GUSTY FOR A PERIOD
THIS AFTERNOON INTO THE EARLY EVENING WITH GUSTS INTO THE TEENS TO
20 KNOTS. WINDS WILL WEAKEN AS THE EVENING PROGRESSES AND SHOULD
BECOME LIGHT TO CALM OVERNIGHT.
OUTLOOK...
SAT NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
SUN: NO OPERATIONAL IMPACT. NO SIG WX.
SUN NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
MON: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF SHRA...TSRA.
MON NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA.
TUE: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA.
TUE NIGHT-WED: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA.
&&
.FIRE WEATHER...
MINIMAL FIRE WEATHER CONCERNS THROUGH THE WEEKEND AS AN UPPER
LEVEL DISTURBANCE WILL RESULT IN ISOLATED TO SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS TODAY...AND THEN EXPECT FAIR AND DRY
WEATHER TONIGHT INTO SUNDAY.
RELATIVE HUMIDITY VALUES ARE EXPECTED TO LOWER TO 35 TO 50 PERCENT
THIS AFTERNOON...THEN INCREASE TO 85 TO 100 PERCENT TONIGHT WITH
SOME PATCHY FOG IN SOME LOCATIONS. MIN RH VALUES SUNDAY WILL DROP
TO 35 TO 45 PERCENT DURING THE AFTERNOON.
THE WINDS TODAY WILL BE SOUTHWEST TO WEST AT 10 TO 20 MPH AND
WILL BECOME LIGHT AND VARIABLE IN DIRECTION AT 5 MPH OR LESS
TONIGHT. THE WINDS WILL BE FROM THE SOUTH TO SOUTHWEST AT 5 TO 10
MPH ON SUNDAY.
&&
.HYDROLOGY...
ISOLATED TO SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE
FORECAST FOR TODAY INTO EARLY THIS EVENING. MORE SHOWERS AND
THUNDERSTORMS ARE EXPECTED MONDAY INTO MONDAY NIGHT. WIDESPREAD
HEAVY RAINFALL ISN/T EXPECTED...BUT ANY THUNDERSTORM WILL BE
CAPABLE OF PRODUCING LOCALLY HEAVY DOWNPOURS ON MONDAY. THESE
DOWNPOURS WILL CAUSE PONDING OF WATER ON ROADS...AND PERHAPS SOME
POOR DRAINAGE FLOODING OF LOW-LYING AREAS.
SCATTERED SHOWERS ARE EXPECTED INTO THE MID WEEK WITH AN UPPER
LEVEL LOW...BUT LITTLE IMPACT ON THE RIVERS IS EXPECTED IN THE
ALY HYDRO SERVICE AREA.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
MA...NONE.
VT...NONE.
&&
$$
SYNOPSIS...WASULA
NEAR TERM...FRUGIS/WASULA
SHORT TERM...WASULA
LONG TERM...IAA
AVIATION...IAA
FIRE WEATHER...BGM/WASULA
HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
641 AM EDT SAT AUG 1 2015
.SYNOPSIS...
A STALLED FRONTAL BOUNDARY WILL KEEP THE HIGHEST CHANCE OF SHOWERS
AND THUNDERSTORMS ACROSS THE SOUTHEAST MIDLANDS THROUGH THE
WEEKEND. ABOVE NORMAL TEMPERATURES ARE EXPECTED THIS WEEKEND AND
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPPER RIDGE OUT WEST WITH BROAD TROUGH FROM THE GREAT LAKES TO
THE EAST COAST. SURFACE ANALYSIS AT 07Z INDICATES WEAK FRONTAL
BOUNDARY ACROSS CENTRAL SOUTH CAROLINA. SHARP MOISTURE GRADIENT
ACROSS THE REGION WITH DEEPER MOISTURE TO THE EAST. WEAK FRONT TO
SHIFT TOWARD THE COAST TODAY. APPROACH OF WEAK SHORT WAVE TROUGH
AND WEAK TO MODERATE INSTABILITY SUPPORTS LOW CHANCE POPS IN THE
SOUTHEAST MIDLANDS...MAINLY THIS AFTERNOON. LATEST HRRR SHOWS
SCATTERED COVERAGE IN THAT REGION. RELATIVELY HIGH PRECIPITABLE
WATER REMAINS IN THAT AREA AT LEAST EARLY THIS AFTERNOON AND
SOUNDING ANALYSIS SUGGEST ANY THUNDERSTORMS THAT DEVELOP COULD
PRODUCE HEAVY RAIN ALONG WITH SLOW MOVEMENT. IF DRIER AIR FROM THE
CENTRAL MIDLANDS GETS ENTRAINED INTO STORMS...LOW THREAT STRONG
WINDS ALSO. THREAT IN THE CENTRAL MIDLANDS AND WEST LOW AS
SOUNDINGS APPEAR CAPPED AND DRIER. MET HAS COOL BIAS WITH MAX
TEMPERATURES SO WENT CLOSER TO MAV/ECS GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
THE WEAK FRONTAL BOUNDARY WILL REMAIN ACROSS EASTERN SOUTH
CAROLINA THROUGH THE PERIOD. MODELS APPEARS TO BE DRIER ACROSS
CENTRAL SOUTH CAROLINA AND CSRA AND SOUNDINGS LIKELY CAPPED. SO
LOWERED POPS SLIGHTLY THROUGH THE PERIOD...WIDELY SCATTERED
CONVECTION CONFINED MAINLY IN THE EAST MIDLANDS...LOWER CSRA.
MAX TEMPERATURES MAINLY IN THE MID TO UPPER 90S...LOWS UPPER 60S
TO MID 70S.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
MODELS HAVE BEEN CONSISTENT SHOWING A RIDGE OVER THE CENTRAL US
WITH A BROAD TROUGH ALONG THE EAST COAST. THE FRONTAL BOUNDARY
WILL REMAIN ALONG THE COAST THROUGH EARLY NEXT WEEK BEFORE
DISSIPATING. THE GFS AND ECMWF ARE IN GOOD AGREEMENT THROUGH
WEDNESDAY...KEEPING THE AREA MAINLY DRY. MOISTURE RETURNS TO THE
REGION TOWARDS THE END OF THE PERIOD FAVORING CLIMATOLOGY FOR
POPS. HIGH TEMPERATURES IN THE MID 90S ARE EXPECTED WITH A GRADUAL
WARMING TREND NEXT WEEK.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
VFR EXPECTED AT CAE/CUB...WITH RESTRICTIONS POSSIBLE AT TIMES AT
OGB/AGS/DNL IN POSSIBLE FOG/STRATUS AND/OR CONVECTION.
TIGHT ATMOSPHERIC MOISTURE GRADIENT NOTED CURRENTLY ACROSS THE
REGION...WITH PRECIPITABLE WATER VALUES RANGING FROM 1.3 INCHES NEAR
OUR NORTHERN FORECAST AREA (FA) TO AROUND 2 INCHES NEAR THE
SOUTHERN FA. SURFACE BOUNDARY GENERALLY STRETCHES ACROSS SOUTHERN
PORTIONS OF THE MIDLANDS AND CSRA WHERE IT IS EXPECTED TO REMAIN
NEARLY STATIONARY TODAY. STRATUS AND FOG CURRENTLY RELEGATED MAINLY
TO PORTIONS OF CENTRAL AND SOUTH GA AND THE SOUTH COAST OF SC. STILL
SOME POSSIBILITIES THAT THIS COULD SHIFT NORTH INTO THE AGS/DNL/OGB
TERMINALS IN THE NEAR TERM...BUT CONFIDENCE LOW.
AFTER ANY MORNING FOG/STRATUS DISSIPATES...FOCUS WILL SHIFT TO
DIURNAL CONVECTION WHICH IS EXPECTED TO BE FOCUSED ALONG AND SOUTH
OF THE NEARLY STATIONARY BOUNDARY ACROSS OUR SOUTHERN FA. FOR
NOW...WILL INDICATE VCSH AT AGS/DNL/OGB.
EXTENDED AVIATION OUTLOOK...
RESTRICTIONS POSSIBLE IN LATE NIGHT/EARLY MORNING FOG/STRATUS...WITH
A CHANCE OF DIURNAL THUNDERSTORMS...MAINLY OGB/AGS/DNL...SUNDAY.
LOW POTENTIAL FOR AFTERNOON AND EVENING CONVECTION MONDAY AND
TUESDAY...THOUGH EARLY MORNING FOG WILL BE POSSIBLE AT THE FOG PRONE
SITES AGS AND OGB.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1100 AM EDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 1100 AM EDT SAT AUG 1 2015
GRIDS HAVE BEEN TOUCHED UP BASED ON RECENT OBSERVATIONS AND
TRENDS. A WEAK MOISTURE STARVED COLD FRONT IS DROPPING SOUTH
ACROSS THE REGION TODAY AND HAVE LITTLE EFFECT OTHER THAN SHIFT
WINDS TO MORE OF A NORTHWEST DIRECTION BEHIND IT AS ANOTHER SFC
HIGH BUILDS IN. THIS HIGH WILL ALSO KEEP DEWPOINTS IN THE UPPER
50S TO LOWER 60S RANGE THROUGH TONIGHT.
UPDATE ISSUED AT 715 AM EDT SAT AUG 1 2015
TOUCHED UP THE GRIDS PER THE LATEST OBS AND TRENDS. THESE HAVE
BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 305 AM EDT SAT AUG 1 2015
06Z SFC ANALYSIS SHOWS THAT HIGH PRESSURE REMAINS IN CONTROL OF
EAST KENTUCKY/S WEATHER THIS EARLY MORNING. THIS HIGH HAS KEPT
CLOUD COVER TO A MINIMUM AND IS SUPPORTING A DECENT RIDGE TO
VALLEY TEMPERATURE SPLIT ON THE ORDER OF 5 TO 10 DEGREES. AT THE
SAME TIME DEWPOINTS ARE RUNNING IN THE LOWER 60S. AS TEMPERATURES
CONTINUE TO RADIATE LOWER FOR THE REST OF THE NIGHT THE DEWPOINTS
WILL ALSO CREEP DOWN...BUT IN THE DEEPER VALLEYS PROBABLY NOT FAST
ENOUGH TO PREVENT THE DEVELOPMENT OF FOG...ESPECIALLY NEAR RIVERS
AND BODIES OF WATER. WINDS WILL BE LIGHT THROUGH DAWN PERHAPS
CONTRIBUTING TO THE LOCALLY DENSE FOG IN THE MORE SHELTERED RIVER
VALLEY SPOTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE LONGWAVE PATTERN
AS THEY ALL DEPICT A SLOWLY DEEPENING...LARGE TROUGH THROUGH THE
NORTHEAST PORTION OF THE CONTINENT STRETCHING SOUTH THROUGH THE
OHIO VALLEY OVER THE WEEKEND. THE NORTHWEST FLOW ASSOCIATED WITH
THIS WILL BRING MINOR SHORTWAVES OVER KENTUCKY DURING THE PERIOD
BUT NOT MUCH IN THE WAY OF MESOSCALE AMPLIFICATION UNTIL PERHAPS
SUNDAY AFTERNOON WHEN A HEALTHIER ONE PASSES BY TO THE NORTH. THE
NAM CONTINUES TO BE ON THE STRONGER SIDE OF THE MODEL SPECTRUM
WITH THE LARGER TROUGH AND THIS WAVE LATE IN THE PERIOD.
ACCORDINGLY...HAVE GONE WITH MORE OF A MODEL BLEND FAVORING A MIX
OF THE ECMWF AND GFS OUTSIDE OF THE NEAR TERM WHERE THE HRRR AND
NAM12 ARE REASONABLE.
SENSIBLE WEATHER WILL FEATURE A VERY PLEASANT MID SUMMER WEEKEND
AS THE AFTERNOON WARMTH IS KEPT COMFORTABLE BY RELATIVELY LOW
HUMIDITIES WROUGHT BY A MIDDAY AND AFTERNOON MIX DOWN OF DRIER
AIR FROM THE MID LEVELS. THIS WILL KEEP CLOUD COVER TO A MINIMUM
THROUGH THE PERIOD AND ALSO LEAD TO ANOTHER NIGHT OF GOOD
RADIATIONAL COOLING FOR SUNDAY MORNING. SIMILARLY...PATCHY FOG
WILL LIKELY BE LIMITED TO THE DEEPER RIVER VALLEY LOCATIONS BOTH
THIS MORNING AND SUNDAY MORNING...THOUGH LOCALLY DENSE POCKETS
WILL BE POSSIBLE AS WELL.
AGAIN USED THE SHORTBLEND MODEL AS A STARTING POINT FOR THE
T/TD/WIND GRIDS THROUGH THE DAY FOLLOWED BY THE SUPERBLEND INTO
SUNDAY. DID MAKE SOME SIGNIFICANT ADJUSTMENTS TO TEMPERATURES
THIS MORNING AND TONIGHT WITH RESPECT TO RIDGE AND VALLEY
DIFFERENCES ONCE...AND AS...THE INVERSION IS IN PLACE. AS FOR
POPS...KEPT THEM LOW AND IN LINE WITH THE DRIER MET GUIDANCE.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 358 AM EDT SAT AUG 1 2015
THE EXTENDED PERIOD BEGINS WITH THE UPPER LEVEL PATTERN FEATURING A
RIDGE OVER THE WESTERN CONUS AND A TROUGH OVER THE EAST AND A
CLOSED LOW CENTERED JUST SOUTH OF THE HUDSON BAY AREA. THIS
PATTERN...THOUGH WITH SOME SHIFTING OF FEATURES EACH
DAY...REMAINS IN PLACE FOR JUST ABOUT THE ENTIRE EXTENDED. TO
START THE EXTENDED...A WEAK SHORTWAVE WILL PASS THROUGH THE LOWER
GREAT LAKES REGION BRINGING A SURFACE COLD FRONT ACROSS NORTHERN
KENTUCKY AND THE CHANCE FOR SOME AFTERNOON SHOWERS AND
THUNDERSTORMS. BY TUESDAY...A SURFACE STATIONARY BOUNDARY SETS UP
ACROSS SOUTHERN OH...IN...AND IL ALLOWING FOR A FOCUS OF SHOWER
AND THUNDERSTORM DEVELOPMENT ALONG NORTHERN KENTUCKY ON MONDAY AND
TUESDAY.
THROUGH THE REST OF THE EXTENDED...THE PATTERN IN PLACE WILL BE
FAVORABLE FOR MCS/S IN THIS NORTHWEST FLOW. THIS HOLDS TRUE
THROUGH TUESDAY AND THURSDAY PERIOD. HAVE KEPT THE SUGGESTED POPS
INHERITED BY THE SUPER BLEND WITH INSTABILITY AND MOISTURE IN
PLACE...THIS SEEMS LIKELY ACROSS EASTERN KENTUCKY...ESPECIALLY
WITH THE INCONSISTENCY IN THE GFS AND EURO. BY THE WEDNESDAY
EVENING AND WEDNESDAY NIGHT PERIOD...A BETTER COMPLEX IS SEEMS
POISED TO MOVE INTO THE AREA. HOWEVER...AS STATED EARLIER...THE GFS
AND EURO HAVE BEEN INCONSISTENT WITH THE TRACK AND TIMING THIS
LATE IN THE EXTENDED AS RECENT RUNS HAVE THE UPPER TROUGH PUSHING
FURTHER SOUTH AS WELL AS THE SURFACE GRADIENT. OVERALL...THE DAY
5...6 AND 7 PERIOD SEEMS QUITE ACTIVE AND WILL KEEP THE HIGH
CHANCE POPS ADVERTISED BY THE SUPER BLEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 735 AM EDT SAT AUG 1 2015
HIGH PRESSURE WILL KEEP VFR CONDITIONS IN THE TAF FORECAST FOR
ALL SITES THROUGH THE PERIOD. OUTSIDE OF THE OFFICIAL TAF
SITES...PATCHY FOG AGAIN WILL BE FOUND IN THE LOWER ELEVATIONS
TOWARDS DAWN SUNDAY MORNING...PERHAPS BECOMING LOCALLY DENSE FOR
A BRIEF TIME. WINDS THROUGH THE PERIOD WILL BE LIGHT AND VARIABLE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
734 AM EDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 715 AM EDT SAT AUG 1 2015
TOUCHED UP THE GRIDS PER THE LATEST OBS AND TRENDS. THESE HAVE
BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 305 AM EDT SAT AUG 1 2015
06Z SFC ANALYSIS SHOWS THAT HIGH PRESSURE REMAINS IN CONTROL OF
EAST KENTUCKY/S WEATHER THIS EARLY MORNING. THIS HIGH HAS KEPT
CLOUD COVER TO A MINIMUM AND IS SUPPORTING A DECENT RIDGE TO
VALLEY TEMPERATURE SPLIT ON THE ORDER OF 5 TO 10 DEGREES. AT THE
SAME TIME DEWPOINTS ARE RUNNING IN THE LOWER 60S. AS TEMPERATURES
CONTINUE TO RADIATE LOWER FOR THE REST OF THE NIGHT THE DEWPOINTS
WILL ALSO CREEP DOWN...BUT IN THE DEEPER VALLEYS PROBABLY NOT FAST
ENOUGH TO PREVENT THE DEVELOPMENT OF FOG...ESPECIALLY NEAR RIVERS
AND BODIES OF WATER. WINDS WILL BE LIGHT THROUGH DAWN PERHAPS
CONTRIBUTING TO THE LOCALLY DENSE FOG IN THE MORE SHELTERED RIVER
VALLEY SPOTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE LONGWAVE PATTERN
AS THEY ALL DEPICT A SLOWLY DEEPENING...LARGE TROUGH THROUGH THE
NORTHEAST PORTION OF THE CONTINENT STRETCHING SOUTH THROUGH THE
OHIO VALLEY OVER THE WEEKEND. THE NORTHWEST FLOW ASSOCIATED WITH
THIS WILL BRING MINOR SHORTWAVES OVER KENTUCKY DURING THE PERIOD
BUT NOT MUCH IN THE WAY OF MESOSCALE AMPLIFICATION UNTIL PERHAPS
SUNDAY AFTERNOON WHEN A HEALTHIER ONE PASSES BY TO THE NORTH. THE
NAM CONTINUES TO BE ON THE STRONGER SIDE OF THE MODEL SPECTRUM
WITH THE LARGER TROUGH AND THIS WAVE LATE IN THE PERIOD.
ACCORDINGLY...HAVE GONE WITH MORE OF A MODEL BLEND FAVORING A MIX
OF THE ECMWF AND GFS OUTSIDE OF THE NEAR TERM WHERE THE HRRR AND
NAM12 ARE REASONABLE.
SENSIBLE WEATHER WILL FEATURE A VERY PLEASANT MID SUMMER WEEKEND
AS THE AFTERNOON WARMTH IS KEPT COMFORTABLE BY RELATIVELY LOW
HUMIDITIES WROUGHT BY A MIDDAY AND AFTERNOON MIX DOWN OF DRIER
AIR FROM THE MID LEVELS. THIS WILL KEEP CLOUD COVER TO A MINIMUM
THROUGH THE PERIOD AND ALSO LEAD TO ANOTHER NIGHT OF GOOD
RADIATIONAL COOLING FOR SUNDAY MORNING. SIMILARLY...PATCHY FOG
WILL LIKELY BE LIMITED TO THE DEEPER RIVER VALLEY LOCATIONS BOTH
THIS MORNING AND SUNDAY MORNING...THOUGH LOCALLY DENSE POCKETS
WILL BE POSSIBLE AS WELL.
AGAIN USED THE SHORTBLEND MODEL AS A STARTING POINT FOR THE
T/TD/WIND GRIDS THROUGH THE DAY FOLLOWED BY THE SUPERBLEND INTO
SUNDAY. DID MAKE SOME SIGNIFICANT ADJUSTMENTS TO TEMPERATURES
THIS MORNING AND TONIGHT WITH RESPECT TO RIDGE AND VALLEY
DIFFERENCES ONCE...AND AS...THE INVERSION IS IN PLACE. AS FOR
POPS...KEPT THEM LOW AND IN LINE WITH THE DRIER MET GUIDANCE.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 358 AM EDT SAT AUG 1 2015
THE EXTENDED PERIOD BEGINS WITH THE UPPER LEVEL PATTERN FEATURING A
RIDGE OVER THE WESTERN CONUS AND A TROUGH OVER THE EAST AND A
CLOSED LOW CENTERED JUST SOUTH OF THE HUDSON BAY AREA. THIS
PATTERN...THOUGH WITH SOME SHIFTING OF FEATURES EACH
DAY...REMAINS IN PLACE FOR JUST ABOUT THE ENTIRE EXTENDED. TO
START THE EXTENDED...A WEAK SHORTWAVE WILL PASS THROUGH THE LOWER
GREAT LAKES REGION BRINGING A SURFACE COLD FRONT ACROSS NORTHERN
KENTUCKY AND THE CHANCE FOR SOME AFTERNOON SHOWERS AND
THUNDERSTORMS. BY TUESDAY...A SURFACE STATIONARY BOUNDARY SETS UP
ACROSS SOUTHERN OH...IN...AND IL ALLOWING FOR A FOCUS OF SHOWER
AND THUNDERSTORM DEVELOPMENT ALONG NORTHERN KENTUCKY ON MONDAY AND
TUESDAY.
THROUGH THE REST OF THE EXTENDED...THE PATTERN IN PLACE WILL BE
FAVORABLE FOR MCS/S IN THIS NORTHWEST FLOW. THIS HOLDS TRUE
THROUGH TUESDAY AND THURSDAY PERIOD. HAVE KEPT THE SUGGESTED POPS
INHERITED BY THE SUPER BLEND WITH INSTABILITY AND MOISTURE IN
PLACE...THIS SEEMS LIKELY ACROSS EASTERN KENTUCKY...ESPECIALLY
WITH THE INCONSISTENCY IN THE GFS AND EURO. BY THE WEDNESDAY
EVENING AND WEDNESDAY NIGHT PERIOD...A BETTER COMPLEX IS SEEMS
POISED TO MOVE INTO THE AREA. HOWEVER...AS STATED EARLIER...THE GFS
AND EURO HAVE BEEN INCONSISTENT WITH THE TRACK AND TIMING THIS
LATE IN THE EXTENDED AS RECENT RUNS HAVE THE UPPER TROUGH PUSHING
FURTHER SOUTH AS WELL AS THE SURFACE GRADIENT. OVERALL...THE DAY
5...6 AND 7 PERIOD SEEMS QUITE ACTIVE AND WILL KEEP THE HIGH
CHANCE POPS ADVERTISED BY THE SUPER BLEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 735 AM EDT SAT AUG 1 2015
HIGH PRESSURE WILL KEEP VFR CONDITIONS IN THE TAF FORECAST FOR
ALL SITES THROUGH THE PERIOD. OUTSIDE OF THE OFFICIAL TAF
SITES...PATCHY FOG AGAIN WILL BE FOUND IN THE LOWER ELEVATIONS
TOWARDS DAWN SUNDAY MORNING...PERHAPS BECOMING LOCALLY DENSE FOR
A BRIEF TIME. WINDS THROUGH THE PERIOD WILL BE LIGHT AND VARIABLE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS GRAY ME
900 AM EDT SAT AUG 1 2015
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA TODAY...BRINGING ANOTHER THREAT
FOR SHOWERS AND THUNDERSTORMS. TEMPERATURES AND HUMIDITY DROP OFF
A LITTLE MORE BEHIND THIS FRONT. SUNDAY SHOULD BE MAINLY DRY AS
HIGH PRESSURE BUILDS ACROSS NEW ENGLAND. WEAK LOW PRESSURE
ALOFT...SITUATED OVER QUEBEC...WILL BRING ANOTHER ROUND SHOWERS OR
STORMS MONDAY AFTERNOON INTO TUESDAY. THE MID TO LATE WEEK PERIOD
WILL REMAIN UNSETTLED WITH A FEW ROUNDS OF SHOWERS OR
THUNDERSTORMS POSSIBLE.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
553AM UPDATE: WILL DIMINISH EARLY MORNING POPS SOME BASED ON
WEAKENING RADAR TREND SEEN WITH INITIAL ECHOES AS THEY ATTEMPT TO
WORK THROUGH NORTHERN VERMONT AND OUTRUN ANY MEANINGFUL MUCAPE
FROM RECENT RAP ANALYSES. EXPECT THAT WE/LL NEED A LITTLE MORNING
SUN AND RESULTANT INSTABILITY TO GET ACTIVITY TO INCREASE IN
COVERAGE/INTENSITY. HAVE ALSO LOWERED TEMPS SOME AND INCLUDED SOME
FOG THROUGH 12Z BASED ON EARLY MORNING OBSERVATIONS SHOWING
LOCALLY DENSE FOG IN THE NORTHERN VALLEYS.
HIGH IMPACT WEATHER POTENTIAL: ISOLATED SEVERE THUNDERSTORM
POTENTIAL THIS AFTERNOON FOR NORTHERN NH AND NORTHERN MAINE.
CURRENT PATTERN: CYCLONIC FLOW THROUGH THE COLUMN HAS FULLY
ENVELOPED THE REGION AS OF THIS WRITING WITH EARLY MORNING WATER
VAPOR IMAGERY SHOWING VERTICALLY STACKED LOW CENTERED OVER HUDSON
BAY. A PARADE OF LOCAL VORTICITY MAXIMA CAN ALSO BE SEEN ROTATING
AROUND THIS FEATURE...WITH A BAND OF ENHANCED MOISTURE STRETCHING
FROM CENTRAL ONTARIO SOUTH AND EAST ACROSS THE NORTHERN GREAT
LAKES...AND JUST STARTING TO SCRAPE NORTHERN NEW ENGLAND. A
SHORTWAVE IS COLLOCATED WITH THE LEADING EDGE OF THIS
MOISTURE...WITH A SURFACE COLD FRONT SPARKING A FEW SHOWERS /AND
EMBEDDED THUNDER/ ACROSS NEW YORK INTO FAR WESTERN NEW ENGLAND.
THE INITIAL SHORTWAVE NORTH OF NEW ENGLAND WILL CONTINUE TO RIDE
NORTH AND EAST...MAKING WAY FOR ANOTHER WAVE...NOW OVER SOUTHERN
ONTARIO...TO PULL EAST AND BE THE FOCUS FOR OUR SENSIBLE WEATHER
TODAY. FORECAST CHALLENGES CENTER AROUND PRECIPITATION POTENTIAL
WITH THIS FEATURE AS WELL AS THE POTENTIAL FOR ANY STRONG/SEVERE
CONVECTION.
THROUGH DAYBREAK: SHOWERS SEEN ON REGIONAL 88D MOSAIC CONTINUE TO
MAKE A RUN AT NORTHERN NEW HAMPSHIRE. EXPECT THAT WE/LL HAVE TO
WAIT FOR THE ACTIVITY IN NEW YORK TO MOVE INTO THE REGION FOR ANY
APPRECIABLE PRECIPITATION...WITH PERHAPS A SPRINKLE POSSIBLE OVER
COOS COUNTY NH THROUGH DAYBREAK. OTHERWISE...JUST SOME MID LEVEL
CLOUDS AND TEMPERATURES RANGING FROM THE LOWER 50S NORTH THROUGH THE
LOWER 60 OVER SOUTHERN NH.
TODAY: ATTENTION TURNS TO UPSTREAM PV ANOMALY MENTIONED ABOVE. THIS
FEATURE LOOKS TO SHARPEN AS IT ROUNDS THE BASE OF THE LONGWAVE
TROUGH AND PUSH INTO NEW ENGLAND. THIS FEATURE WILL BE ACCOMPANIED
BY 50KT JET AT H5 WITH A 1.5PV 85KT SPEED MAX. MODEST HEIGHT FALLS
AND INCREASING DPVA WILL WORK IN TANDEM WITH MODEST MOISTURE
INCREASE AND GOOD LAPSE RATES THROUGH H5 /GIVEN COOL POOL ALOFT/
TO ALLOW CONVECTION CURRENTLY OVER NEW YORK TO EXPAND AS IT MOVES
THROUGH NORTHERN NEW ENGLAND...BEING JOINED LATER BY ADDITIONAL
DEVELOPMENT AHEAD OF THE MID LEVEL TROUGH AXIS/WEAK SURFACE FRONT.
THUS...EXPECT SHRAS TO EXPAND IN COVERAGE...WITH EMBEDDED THUNDER
BECOMING MORE WIDESPREAD AS INSTABILITY GROWS. DEEP LAYER SHEAR IS
IMPRESSIVE...APPROACHING 50KTS IN THE 0-6KM LAYER WITH
LONG AND STRAIGHT...WEST-EAST ORIENTED HODOGRAPHS FAVORING MORE
CELLULAR STRUCTURE TO CELLS GIVEN ORTHOGONAL ORIENTATION OF THE
SHEAR TO THE FORCING FEATURE /FRONT/. INSTABILITY WILL BE
SOMEWHAT LIMITED GIVEN ONLY MODEST LLEVEL MOISTURE RECOVERY...BUT
1K J/KG MLCAPE APPEARS POSSIBLE TO ATTAIN OVER FAR NORTHERN NH /
NW MAINE CLOSER TO THE BEST MID LEVEL LAPSE RATES.
SEVERE WEATHER THREATS: PROFILES HAVE AN INVERTED-V LOOK TO
THEM...WHICH...WITH STRONG WINDS ALOFT SUGGEST A DAMAGING WIND
THREAT...ALTHOUGH MORE LOCALIZED GIVEN THE MORE CELLULAR NATURE TO
THE CONVECTION. WET BULB ZERO HEIGHTS 8-9KFT HIGHLIGHT A HAIL
THREAT AS WELL. TOR THREAT VERY LOW GIVEN THE AFOREMENTIONED
INVERTED-V PROFILES. OVERALL THREAT WILL BE TIED PRIMARILY TO
INSTABILITY...AND THEREFORE WILL BE GREATEST OVER FAR NORTHERN NH
AND NW MAINE...WHICH IS RIGHT IN LINE WITH THE NEW SWODY1 FROM SPC.
WILL INCLUDE ENHANCED WORDING IN THESE LOCATIONS...WITH LESS THUNDER
EMPHASIS FURTHER SOUTH. AND...WHILE THE ACTIVITY FURTHER SOUTH
WILL LIKELY NOT BE SEVERE...WILL MENTION GUSTY WINDS HERE AS WELL
GIVEN INVERTED-V NATURE TO THE PROFILES.
TEMPERATURES: THE INCREASE IN CLOUD COVER WILL SPELL A COOLER
DAY...PARTICULARLY OVER NORTHERN AREAS WHERE CONVECTION WILL BE MOST
WIDESPREAD. HERE...HIGHS WILL REMAIN IN THE 70S. DOWNSLOPE
WESTERLIES WILL PROMOTE HIGHS WELL INTO THE 80S OVER SOUTHEASTERN NH
AND EXTREME SW MAINE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
UPDATE...
HAVE UPDATED THE GRIDS BASED ON CURRENT CONDITIONS AND MESO MODEL
TRENDS. SHORT WAVE AND A WEAK SURFACE FRONT WILL BE DRAPED ACROSS
THE REGION DURING THE MIDDAY HOURS. EXPECT SCATTERED SHOWERS AND
THUNDERSTORMS TO FORM. DEW POINTS REMAIN NEAR 60
DEGREES...SIGNIFICANTLY LOWER THAN A COUPLE DAYS AGO. WARMEST
TEMPERATURES THROUGH THE MIDDAY HOURS WILL BE OVER SOUTHEAST NEW
HAMPSHIRE AND SOUTHWEST MAINE WHERE NEARLY FULL SUNSHINE WILL
CONTINUE THROUGH THE LATE MORNING HOURS.
PREV DISC...
HIGH IMPACT WEATHER POTENTIAL: NONE.
PATTERN/IMPLICATIONS: WESTERLY FLOW ALOFT WILL CONTINUE THROUGH
THE SHORT TERM FORECAST PERIOD ALONG THE SOUTHERN PERIPHERY OF
LONGWAVE TROUGH CENTERED OVER HUDSON BAY. OUR WEATHER WILL BE AT
THE MERCY OF SHORTWAVES ROTATING AROUND THIS FEATURE...WITH A
RELATIVE LULL LIKELY FOR TONIGHT-SUNDAY BEHIND THE STRONGER WAVE
ON SATURDAY AND PRECEDING ANOTHER STRONG WAVE ON MONDAY. DESPITE
RELATIVELY LOW HEIGHTS IN THE TROUGH...LLEVEL TEMPERATURES WILL
REMAIN NEAR NORMAL PROMOTING SURFACE TEMPERATURES NOT TOO FAR FROM
SEASONAL NORMS.
TONIGHT: ANY AFTERNOON CONVECTIVE ACTIVITY SHOULD VERY QUICKLY WANE
WITH PARTIAL CLEARING...ALTHOUGH WITH DEEPER MOISTURE POOL CLOSER TO
THE REGION...DO EXPECT SOME MID LEVEL CLOUDINESS TO HANG AROUND
THROUGH THE NIGHT. LOWS LOOK NOT ALL THAT DISSIMILAR TO TONIGHT
WITH MODEST COOLING TO THE LLEVEL AIRMASS BEHIND DEPARTING COLD
FRONT. GIVEN AT LEAST SOME RAIN ACROSS THE REGION...AND ONLY MODEST
COOLING BEHIND THE DEPARTING COLD FRONT...SOME PATCHY VALLEY FOG
LOOKS TO BE A GOOD BET.
SUNDAY: DEEP CYCLONIC FLOW CONTINUES ACROSS THE REGION AND WHILE
THERE WILL BE LITTLE IN THE WAY OF SYNOPTIC FORCING FOR ASCENT...MID
LEVEL COLD POOL /T5S NEAR -15C/ AND DECENT MOISTURE ALONG SOUTHERN
PERIPHERY OF THE HUDSON BAY VORTEX WILL LIKELY ALLOW SOME AFTERNOON
SHOWERS TO SPARK OVER THE MOUNTAINS. ACTIVITY LOOKS WEAKER AND FAR
LESS WIDESPREAD THAN ON SATURDAY...SO REALLY NOT A BAD DAY EVEN UP
NORTH. OVER SOUTHERN NH/SOUTHWEST MAINE...EXPECT A DIURNAL INCREASE
IN CLOUDS...BUT NO PRECIPITATION. TEMPS ALOFT WILL BE ABOUT 2C
COOLER THAN ON SATURDAY...BUT WITH LIKELY A BIT MORE SUN...SO HIGH
TEMPERATURES LOOK SIMILAR TO THE DAY PREVIOUS...PERHAPS A DEGREE/TWO
COOLER FOR SOUTHEAST NH AND SW MAINE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGH IMPACT WEATHER IN THE EXTENDED WILL BE THREAT OF STRONG TO
SEVERE THUNDERSTORMS MONDAY AFTERNOON INTO MONDAY NIGHT.
500MB PATTERN IS TRENDING TOWARD A MODIFIED +PNA PATTERN WITH
CLOSED LOW STARTING OUR OVER HUDSON AROUND 60N AND EVENTUALLY
SHIFT SWD INTO SRN QUEBEC BY MID WEEK BEFORE SHIFTING THE NE AND
WEAKENING AS IT RUNS INTO N ATLANTIC RIDGING. THIS WILL PULL SOME
COOLER AIR SWD BY MID TO LATE THIS WEEK...AND WILL KEEP THINGS
SOMEWHAT UNSETTLED AS IT PRODUCES CYCLONIC FLOW ALOFT. TOWARD NEXT
WEEKEND THE CORE OF THE JET WILL SHIFT BACK TO THE N...AND COULD
SEE THINGS START TO WARM AGAIN.
SUN NIGHT WILL START WITH BUILDING 500MB RIDGING OVER ME AN THE
CANADIAN MARITIMES WHICH WILL ALLOW FLOW TO SHIFT TO THE SW ANDTAP
INTO WARM AIR...SFC AND MID-LVL JUST TO OUR SW. AFTER AN MAINLY
CLEAR AND SEASONABLY COOL SUN NIGHT MONDAY WILL WARM UP WITH
SHRA/TSRA MOVING INTO NW ZONES IN THE AFTERNOON. AS THE 500 MB
CLOSED LOW DEEPENS TO THE WEST AND HEIGHTS FALL WILL SEE DECENT
INSTABILITY DEVELOP ALONG WITH INCREASED FLOW ALOFT. NAM IS
SUGGESTING BORDERLINE EML MOVING IN OVER THE COASTAL PLAIN BY LATE
MON AFT INTO MON EVE...WHICH WOULD AID IN THE FORMATION OF SEVER
STORMS. AT ANY RATE THUNDERSTORMS...WILL BE A GOOD BET AWAY FROM
THE COAST MON AFTERNOON INTO EVENING. ANOTHER WEAK WAVE SWINGS
AROUND THE CLOSED LOW ON TUE...SO ANOTHER ROUND OF SHRA AND TSRA
POSSIBLE...AS THE COOLER AIR WILL WORK IN BEHIND THIS WAVE
TUESDAY. WED THRU FRI WILL BE PARTLY SUNNY...BUT COLD AIR ALOFT
COULD PRODUCE SCT SHRA...MAYBE A TSRA EACH DAY...ESPECIALLY IN THE
MTNS.
TEMPERATURES WILL START OUT ON THE WARM SIDE MONDAY...AS HIGHS
WILL SURGE BACK INTO THE 85-90 RANGE IN MANY INLAND SPOTS...BUT
SHOULD BE A FEW DEGREES COOLER ON THE COAST...AND ESPECIALLY THE
MID-COAST WHERE SW FLOW INCREASES. IT WILL BE A WARM AND MUGGY MON
NIGHT...WITH TEMPS AND HUMIDITY ON THE HIGHER SIDE TUE...BUT MORE
CLOUDS WILL KEEP TEMPS DOWN A FEW DEGREES. ONCE THE FRONT COMES
THRU IN THE AFTERNOON LOOK FOR OVERNIGHT LOWS TO DROP TO AROUND
NORMAL...LOW-MID 50S N...TO THE LOW 60S IN SRN NH...WITH HIGHS
RUNNING IN THE LOW 70S TO AROUND 80 THRU THE REST OF THE WEEK.
&&
.AVIATION /13Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH SUNDAY/...A COLD FRONT WILL BRING A ROUND OF
SHOWERS AND THUNDERSTORMS TO THE REGION TODAY WITH QUIETER
CONDITIONS WORKING BACK INTO THE REGION TONIGHT.
A BAND OF LIGHT SHOWERS IS WEAKENING AS IT ARRIVES OVER NH AS OF
THIS WRITING. OUTSIDE OF SOME THICKENING MID CLOUDINESS...EXPECT A
FAIRLY QUIET MORNING. SHOWERS AND THUNDERSTORMS WILL INCREASE IN
COVERAGE AND INTENSITY THIS AFTERNOON...WITH THE BEST CHANCES FOR
THUNDER AT HIE/LEB/AUG/RCK WHERE A BRIEF PERIOD OF MVFR/IFR VSBYS IS
POSSIBLE IN A HEAVY DOWNPOUR. WILL INCLUDE VCTS MENTION TO COVER THE
PERIOD MOST LIKELY TO SEE THIS SHRA/TSRA ACTIVITY. THERE IS THE
POTENTIAL FOR A FEW STORMS TO BECOME STRONG TO SEVERE. ACTIVITY WILL
QUICKLY WANE THIS EVENING WITH PARTIAL CLEARING OVERNIGHT. GIVEN
SOME DAYTIME RAINFALL AND ONLY MODEST DRYING OVERNIGHT...EXPECT FOG
WILL ONCE AGAIN IMPACT LEB AND HIE AFTER MIDNIGHT WITH IFR/LIFR
VSBYS.
WINDS: LIGHT WINDS WIL BECOME WEST-SOUTHWESTERLY AND INCREASE TO
10G18KTS FOR THE DAY TODAY BEFORE DIMINISHING TO 5KTS OR LESS FROM
THE NORTHWEST THIS EVENING AND OVERNIGHT TONIGHT.
EXPECT VFR CONDITIONS ON SUNDAY...WITH A DIURNAL INCREASE IN
CUMULUS COVERAGE...AND PERHAPS A SPRINKLE/SHOWER AT HIE.
LONG TERM...MAINLY VFR SUN NIGHT THROUGH TUESDAY...WITH VLY FOG
POSSIBLE EACH NIGHT. SCT SHRA/TSRA WILL IMPACT MOST OF THE
TERMINALS LATE MON AND MON NIGHT.
&&
.MARINE...
SHORT TERM...EXPECT WAVES AND SOUTHERLY WINDS TO REMAIN BELOW
SMALL CRAFT LEVELS THROUGH SUNDAY DESPITE INCREASING SOMEWHAT
DURING THE DAY TODAY AHEAD OF A COLD FRONT.
LONG TERM...PERSISTENT SW FLOW SUNDAY AND MONDAY COULD BRING
HIGHER SWELLS TO THE COASTLINE MONDAY AND MONDAY NIGHT....AND A
SURGE OF SW WINDS COULD APPROACH SCA LVLS FOR A SHORT PERIOD MON
NIGHT.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
625 AM EDT SAT AUG 1 2015
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA TODAY...BRINGING ANOTHER THREAT
FOR SHOWERS AND THUNDERSTORMS. TEMPERATURES AND HUMIDITY DROP OFF
A LITTLE MORE BEHIND THIS FRONT. SUNDAY SHOULD BE MAINLY DRY AS
HIGH PRESSURE BUILDS ACROSS NEW ENGLAND. WEAK LOW PRESSURE
ALOFT...SITUATED OVER QUEBEC...WILL BRING ANOTHER ROUND SHOWERS OR
STORMS MONDAY AFTERNOON INTO TUESDAY. THE MID TO LATE WEEK PERIOD
WILL REMAIN UNSETTLED WITH A FEW ROUNDS OF SHOWERS OR
THUNDERSTORMS POSSIBLE.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
553AM UPDATE: WILL DIMINISH EARLY MORNING POPS SOME BASED ON
WEAKENING RADAR TREND SEEN WITH INITIAL ECHOES AS THEY ATTEMPT TO
WORK THROUGH NORTHERN VERMONT AND OUTRUN ANY MEANINGFUL MUCAPE
FROM RECENT RAP ANALYSES. EXPECT THAT WE/LL NEED A LITTLE MORNING
SUN AND RESULTANT INSTABILITY TO GET ACTIVITY TO INCREASE IN
COVERAGE/INTENSITY. HAVE ALSO LOWERED TEMPS SOME AND INCLUDED SOME
FOG THROUGH 12Z BASED ON EARLY MORNING OBSERVATIONS SHOWING
LOCALLY DENSE FOG IN THE NORTHERN VALLEYS.
HIGH IMPACT WEATHER POTENTIAL: ISOLATED SEVERE THUNDERSTORM
POTENTIAL THIS AFTERNOON FOR NORTHERN NH AND NORTHERN MAINE.
CURRENT PATTERN: CYCLONIC FLOW THROUGH THE COLUMN HAS FULLY
ENVELOPED THE REGION AS OF THIS WRITING WITH EARLY MORNING WATER
VAPOR IMAGERY SHOWING VERTICALLY STACKED LOW CENTERED OVER HUDSON
BAY. A PARADE OF LOCAL VORTICITY MAXIMA CAN ALSO BE SEEN ROTATING
AROUND THIS FEATURE...WITH A BAND OF ENHANCED MOISTURE STRETCHING
FROM CENTRAL ONTARIO SOUTH AND EAST ACROSS THE NORTHERN GREAT
LAKES...AND JUST STARTING TO SCRAPE NORTHERN NEW ENGLAND. A
SHORTWAVE IS COLLOCATED WITH THE LEADING EDGE OF THIS
MOISTURE...WITH A SURFACE COLD FRONT SPARKING A FEW SHOWERS /AND
EMBEDDED THUNDER/ ACROSS NEW YORK INTO FAR WESTERN NEW ENGLAND.
THE INITIAL SHORTWAVE NORTH OF NEW ENGLAND WILL CONTINUE TO RIDE
NORTH AND EAST...MAKING WAY FOR ANOTHER WAVE...NOW OVER SOUTHERN
ONTARIO...TO PULL EAST AND BE THE FOCUS FOR OUR SENSIBLE WEATHER
TODAY. FORECAST CHALLENGES CENTER AROUND PRECIPITATION POTENTIAL
WITH THIS FEATURE AS WELL AS THE POTENTIAL FOR ANY STRONG/SEVERE
CONVECTION.
THROUGH DAYBREAK: SHOWERS SEEN ON REGIONAL 88D MOSAIC CONTINUE TO
MAKE A RUN AT NORTHERN NEW HAMPSHIRE. EXPECT THAT WE/LL HAVE TO
WAIT FOR THE ACTIVITY IN NEW YORK TO MOVE INTO THE REGION FOR ANY
APPRECIABLE PRECIPITATION...WITH PERHAPS A SPRINKLE POSSIBLE OVER
COOS COUNTY NH THROUGH DAYBREAK. OTHERWISE...JUST SOME MID LEVEL
CLOUDS AND TEMPERATURES RANGING FROM THE LOWER 50S NORTH THROUGH THE
LOWER 60 OVER SOUTHERN NH.
TODAY: ATTENTION TURNS TO UPSTREAM PV ANOMALY MENTIONED ABOVE. THIS
FEATURE LOOKS TO SHARPEN AS IT ROUNDS THE BASE OF THE LONGWAVE
TROUGH AND PUSH INTO NEW ENGLAND. THIS FEATURE WILL BE ACCOMPANIED
BY 50KT JET AT H5 WITH A 1.5PV 85KT SPEED MAX. MODEST HEIGHT FALLS
AND INCREASING DPVA WILL WORK IN TANDEM WITH MODEST MOISTURE
INCREASE AND GOOD LAPSE RATES THROUGH H5 /GIVEN COOL POOL ALOFT/
TO ALLOW CONVECTION CURRENTLY OVER NEW YORK TO EXPAND AS IT MOVES
THROUGH NORTHERN NEW ENGLAND...BEING JOINED LATER BY ADDITIONAL
DEVELOPMENT AHEAD OF THE MID LEVEL TROUGH AXIS/WEAK SURFACE FRONT.
THUS...EXPECT SHRAS TO EXPAND IN COVERAGE...WITH EMBEDDED THUNDER
BECOMING MORE WIDESPREAD AS INSTABILITY GROWS. DEEP LAYER SHEAR IS
IMPRESSIVE...APPROACHING 50KTS IN THE 0-6KM LAYER WITH
LONG AND STRAIGHT...WEST-EAST ORIENTED HODOGRAPHS FAVORING MORE
CELLULAR STRUCTURE TO CELLS GIVEN ORTHOGONAL ORIENTATION OF THE
SHEAR TO THE FORCING FEATURE /FRONT/. INSTABILITY WILL BE
SOMEWHAT LIMITED GIVEN ONLY MODEST LLEVEL MOISTURE RECOVERY...BUT
1K J/KG MLCAPE APPEARS POSSIBLE TO ATTAIN OVER FAR NORTHERN NH /
NW MAINE CLOSER TO THE BEST MID LEVEL LAPSE RATES.
SEVERE WEATHER THREATS: PROFILES HAVE AN INVERTED-V LOOK TO
THEM...WHICH...WITH STRONG WINDS ALOFT SUGGEST A DAMAGING WIND
THREAT...ALTHOUGH MORE LOCALIZED GIVEN THE MORE CELLULAR NATURE TO
THE CONVECTION. WET BULB ZERO HEIGHTS 8-9KFT HIGHLIGHT A HAIL
THREAT AS WELL. TOR THREAT VERY LOW GIVEN THE AFOREMENTIONED
INVERTED-V PROFILES. OVERALL THREAT WILL BE TIED PRIMARILY TO
INSTABILITY...AND THEREFORE WILL BE GREATEST OVER FAR NORTHERN NH
AND NW MAINE...WHICH IS RIGHT IN LINE WITH THE NEW SWODY1 FROM SPC.
WILL INCLUDE ENHANCED WORDING IN THESE LOCATIONS...WITH LESS THUNDER
EMPHASIS FURTHER SOUTH. AND...WHILE THE ACTIVITY FURTHER SOUTH
WILL LIKELY NOT BE SEVERE...WILL MENTION GUSTY WINDS HERE AS WELL
GIVEN INVERTED-V NATURE TO THE PROFILES.
TEMPERATURES: THE INCREASE IN CLOUD COVER WILL SPELL A COOLER
DAY...PARTICULARLY OVER NORTHERN AREAS WHERE CONVECTION WILL BE MOST
WIDESPREAD. HERE...HIGHS WILL REMAIN IN THE 70S. DOWNSLOPE
WESTERLIES WILL PROMOTE HIGHS WELL INTO THE 80S OVER SOUTHEASTERN NH
AND EXTREME SW MAINE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
HIGH IMPACT WEATHER POTENTIAL: NONE.
PATTERN/IMPLICATIONS: WESTERLY FLOW ALOFT WILL CONTINUE THROUGH
THE SHORT TERM FORECAST PERIOD ALONG THE SOUTHERN PERIPHERY OF
LONGWAVE TROUGH CENTERED OVER HUDSON BAY. OUR WEATHER WILL BE AT
THE MERCY OF SHORTWAVES ROTATING AROUND THIS FEATURE...WITH A
RELATIVE LULL LIKELY FOR TONIGHT-SUNDAY BEHIND THE STRONGER WAVE
ON SATURDAY AND PRECEDING ANOTHER STRONG WAVE ON MONDAY. DESPITE
RELATIVELY LOW HEIGHTS IN THE TROUGH...LLEVEL TEMPERATURES WILL
REMAIN NEAR NORMAL PROMOTING SURFACE TEMPERATURES NOT TOO FAR FROM
SEASONAL NORMS.
TONIGHT: ANY AFTERNOON CONVECTIVE ACTIVITY SHOULD VERY QUICKLY WANE
WITH PARTIAL CLEARING...ALTHOUGH WITH DEEPER MOISTURE POOL CLOSER TO
THE REGION...DO EXPECT SOME MID LEVEL CLOUDINESS TO HANG AROUND
THROUGH THE NIGHT. LOWS LOOK NOT ALL THAT DISSIMILAR TO TONIGHT
WITH MODEST COOLING TO THE LLEVEL AIRMASS BEHIND DEPARTING COLD
FRONT. GIVEN AT LEAST SOME RAIN ACROSS THE REGION...AND ONLY MODEST
COOLING BEHIND THE DEPARTING COLD FRONT...SOME PATCHY VALLEY FOG
LOOKS TO BE A GOOD BET.
SUNDAY: DEEP CYCLONIC FLOW CONTINUES ACROSS THE REGION AND WHILE
THERE WILL BE LITTLE IN THE WAY OF SYNOPTIC FORCING FOR ASCENT...MID
LEVEL COLD POOL /T5S NEAR -15C/ AND DECENT MOISTURE ALONG SOUTHERN
PERIPHERY OF THE HUDSON BAY VORTEX WILL LIKELY ALLOW SOME AFTERNOON
SHOWERS TO SPARK OVER THE MOUNTAINS. ACTIVITY LOOKS WEAKER AND FAR
LESS WIDESPREAD THAN ON SATURDAY...SO REALLY NOT A BAD DAY EVEN UP
NORTH. OVER SOUTHERN NH/SOUTHWEST MAINE...EXPECT A DIURNAL INCREASE
IN CLOUDS...BUT NO PRECIPITATION. TEMPS ALOFT WILL BE ABOUT 2C
COOLER THAN ON SATURDAY...BUT WITH LIKELY A BIT MORE SUN...SO HIGH
TEMPERATURES LOOK SIMILAR TO THE DAY PREVIOUS...PERHAPS A DEGREE/TWO
COOLER FOR SOUTHEAST NH AND SW MAINE.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGH IMPACT WEATHER IN THE EXTENDED WILL BE THREAT OF STRONG TO
SEVERE THUNDERSTORMS MONDAY AFTERNOON INTO MONDAY NIGHT.
500MB PATTERN IS TRENDING TOWARD A MODIFIED +PNA PATTERN WITH
CLOSED LOW STARTING OUR OVER HUDSON AROUND 60N AND EVENTUALLY
SHIFT SWD INTO SRN QUEBEC BY MID WEEK BEFORE SHIFTING THE NE AND
WEAKENING AS IT RUNS INTO N ATLANTIC RIDGING. THIS WILL PULL SOME
COOLER AIR SWD BY MID TO LATE THIS WEEK...AND WILL KEEP THINGS
SOMEWHAT UNSETTLED AS IT PRODUCES CYCLONIC FLOW ALOFT. TOWARD NEXT
WEEKEND THE CORE OF THE JET WILL SHIFT BACK TO THE N...AND COULD
SEE THINGS START TO WARM AGAIN.
SUN NIGHT WILL START WITH BUILDING 500MB RIDGING OVER ME AN THE
CANADIAN MARITIMES WHICH WILL ALLOW FLOW TO SHIFT TO THE SW ANDTAP
INTO WARM AIR...SFC AND MID-LVL JUST TO OUR SW. AFTER AN MAINLY
CLEAR AND SEASONABLY COOL SUN NIGHT MONDAY WILL WARM UP WITH
SHRA/TSRA MOVING INTO NW ZONES IN THE AFTERNOON. AS THE 500 MB
CLOSED LOW DEEPENS TO THE WEST AND HEIGHTS FALL WILL SEE DECENT
INSTABILITY DEVELOP ALONG WITH INCREASED FLOW ALOFT. NAM IS
SUGGESTING BORDERLINE EML MOVING IN OVER THE COASTAL PLAIN BY LATE
MON AFT INTO MON EVE...WHICH WOULD AID IN THE FORMATION OF SEVER
STORMS. AT ANY RATE THUNDERSTORMS...WILL BE A GOOD BET AWAY FROM
THE COAST MON AFTERNOON INTO EVENING. ANOTHER WEAK WAVE SWINGS
AROUND THE CLOSED LOW ON TUE...SO ANOTHER ROUND OF SHRA AND TSRA
POSSIBLE...AS THE COOLER AIR WILL WORK IN BEHIND THIS WAVE
TUESDAY. WED THRU FRI WILL BE PARTLY SUNNY...BUT COLD AIR ALOFT
COULD PRODUCE SCT SHRA...MAYBE A TSRA EACH DAY...ESPECIALLY IN THE
MTNS.
TEMPERATURES WILL START OUT ON THE WARM SIDE MONDAY...AS HIGHS
WILL SURGE BACK INTO THE 85-90 RANGE IN MANY INLAND SPOTS...BUT
SHOULD BE A FEW DEGREES COOLER ON THE COAST...AND ESPECIALLY THE
MID-COAST WHERE SW FLOW INCREASES. IT WILL BE A WARM AND MUGGY MON
NIGHT...WITH TEMPS AND HUMIDITY ON THE HIGHER SIDE TUE...BUT MORE
CLOUDS WILL KEEP TEMPS DOWN A FEW DEGREES. ONCE THE FRONT COMES
THRU IN THE AFTERNOON LOOK FOR OVERNIGHT LOWS TO DROP TO AROUND
NORMAL...LOW-MID 50S N...TO THE LOW 60S IN SRN NH...WITH HIGHS
RUNNING IN THE LOW 70S TO AROUND 80 THRU THE REST OF THE WEEK.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH SUNDAY/...A COLD FRONT WILL BRING A ROUND OF
SHOWERS AND THUNDERSTORMS TO THE REGION TODAY WITH QUIETER
CONDITIONS WORKING BACK INTO THE REGION TONIGHT.
A BAND OF LIGHT SHOWERS IS WEAKENING AS IT ARRIVES OVER NH AS OF
THIS WRITING. OUTSIDE OF SOME THICKENING MID CLOUDINESS...EXPECT A
FAIRLY QUIET MORNING. SHOWERS AND THUNDERSTORMS WILL INCREASE IN
COVERAGE AND INTENSITY THIS AFTERNOON...WITH THE BEST CHANCES FOR
THUNDER AT HIE/LEB/AUG/RCK WHERE A BRIEF PERIOD OF MVFR/IFR VSBYS IS
POSSIBLE IN A HEAVY DOWNPOUR. WILL INCLUDE VCTS MENTION TO COVER THE
PERIOD MOST LIKELY TO SEE THIS SHRA/TSRA ACTIVITY. THERE IS THE
POTENTIAL FOR A FEW STORMS TO BECOME STRONG TO SEVERE. ACTIVITY WILL
QUICKLY WANE THIS EVENING WITH PARTIAL CLEARING OVERNIGHT. GIVEN
SOME DAYTIME RAINFALL AND ONLY MODEST DRYING OVERNIGHT...EXPECT FOG
WILL ONCE AGAIN IMPACT LEB AND HIE AFTER MIDNIGHT WITH IFR/LIFR
VSBYS.
WINDS: LIGHT WINDS WIL BECOME WEST-SOUTHWESTERLY AND INCREASE TO
10G18KTS FOR THE DAY TODAY BEFORE DIMINISHING TO 5KTS OR LESS FROM
THE NORTHWEST THIS EVENING AND OVERNIGHT TONIGHT.
EXPECT VFR CONDITIONS ON SUNDAY...WITH A DIURNAL INCREASE IN
CUMULUS COVERAGE...AND PERHAPS A SPRINKLE/SHOWER AT HIE.
LONG TERM...MAINLY VFR SUN NIGHT THROUGH TUESDAY...WITH VLY FOG
POSSIBLE EACH NIGHT. SCT SHRA/TSRA WILL IMPACT MOST OF THE
TERMINALS LATE MON AND MON NIGHT.
&&
.MARINE...
SHORT TERM...EXPECT WAVES AND SOUTHERLY WINDS TO REMAIN BELOW
SMALL CRAFT LEVELS THROUGH SUNDAY DESPITE INCREASING SOMEWHAT
DURING THE DAY TODAY AHEAD OF A COLD FRONT.
LONG TERM...PERSISTENT SW FLOW SUNDAY AND MONDAY COULD BRING
HIGHER SWELLS TO THE COASTLINE MONDAY AND MONDAY NIGHT....AND A
SURGE OF SW WINDS COULD APPROACH SCA LVLS FOR A SHORT PERIOD MON
NIGHT.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
AVIATION...ARNOTT
AREA FORECAST DISCUSSION
NWS DULUTH MN
852 AM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 845 AM CDT SAT AUG 1 2015
CLEAR SKIES COVERED THE NORTHLAND EARLY THIS MORNING WITH A LITTLE
MID LEVEL CLOUD NEAR OR JUST SOUTH OF THE BRAINERD LAKES REGION.
AN EARLY LOOK AT SOME OF THE HIGH RES CAMS SHOWED AN AREA OF
SHOWERS DEVELOPING NEAR AND JUST SOUTH OF HIGHWAY 2 IN MINNESOTA
LATE MORNING/EARLY AFTERNOON...THEN MOVING SOUTHEAST. THERE IS
SOME ACCAS OVER PORTIONS OF EASTERN NORTH DAKOTA AND MOST OF THOSE
MODELS INDICATE THAT IS NEAR WHERE THE SHOWERS WILL INITIALLY
FORM.
WE WILL NOT UPDATE TO INCLUDE SHOWERS AT THIS TIME. NOT ALL MODELS
INDICATE THESE SHOWERS WILL DEVELOP AND THE LATEST SPC HRRR OVER
THE PAST FEW RUNS HAVE DELAYED THE ARRIVAL OF THESE SHOWERS AND
HAVE CUT BACK ON THE COVERAGE. WE WILL MONITOR AND UPDATE AS
NEEDED.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 339 AM CDT SAT AUG 1 2015
AT 400 AM...SKIES WERE MOSTLY CLEAR ACROSS THE NORTHLAND.
TEMPERATURES RANGED FROM THE UPPER 40S TO THE MIDDLE 50S. A FEW
LOCATIONS NEAR LAKE SUPERIOR WERE IN THE LOWER 60S WITH LIGHT
WINDS.
THE FOCUS FOR TODAY THROUGH SUNDAY WILL BE TRYING TO RESOLVE
VARIOUS PRECIPITATION EVENTS. THE SHOWERS THAT MOVED THROUGH THE
ARROWHEAD EARLIER THIS MORNING WERE FINALLY PUSHING OFF TO THE
SOUTHEAST ACROSS LAKE SUPERIOR. THE LATEST HIGH RESOLUTION
MODELS GENERALLY FAVOR A MOSTLY DRY FORECAST FOR THE AREA
TODAY...ALTHOUGH WE WILL CONTINUE TO CARRY A SMALL POP ACROSS THE
FAR NORTH AND FAR SOUTH/SW DURING THE AFTERNOON. THE BETTER CHANCE
FOR SHOWERS AND THUNDERSTORMS WILL ARRIVE TONIGHT...AS A WEAK AREA
OF LOW PRESSURE AND WARM FRONT MOVES SOUTHEASTWARD THROUGH CENTRAL
MN. THIS WEAK FEATURE WILL SET THE STAGE FOR THUNDERSTORMS...WITH
A COLD FRONT ACROSS THE INTERNATIONAL BORDER SETTING THE STAGE FOR
SHOWERS AND THUNDERSTORMS ACROSS THE NORTH.
IN TERMS OF SPECIFICS...TODAY SHOULD BE A GENERALLY DRY DAY. AGAIN
WE WILL CARRY SMALL POPS FAR NORTH AND SOUTH. HIGH TEMPERATURES
WILL GENERALLY BE AROUND 80 DEGREES WITH WEST WINDS.
TONIGHT...SHOWERS AND THUNDERSTORMS SHOULD INCREASE IN NUMBER...
ESPECIALLY ACROSS THE NORTH AND THE SOUTH. CENTRAL PORTIONS OF THE
CWA SHOULD SEE THE LEAST SHOWER AND THUNDERSTORM ACTIVITY. THINK
SOME OF THE STORMS IN THE SOUTH COULD BE STRONG OVERNIGHT...AND
THERE COULD BE A SEVERE THUNDERSTORM AS WELL. THE PRIMARY THREAT
WOULD BE SOUTH OF A BRAINERD TO HAYWARD LINE...WITH HAIL AND
STRONG WINDS BEING THE PRIMARY THREATS. OVERNIGHT LOWS WILL RANGE
FROM THE 50S TO LOWER 60S.
ON SUNDAY...WE SHOULD CONTINUE TO SEE SCATTERED SHOWERS AND
THUNDERSTORMS...ESPECIALLY ACROSS THE ARROWHEAD...TWIN PORTS AND
NORTHWESTERN WISCONSIN. LESSER CHANCES ARE EXPECTED FURTHER WEST.
HIGHS WILL BE A LITTLE COOLER ON SUNDAY...WITH HIGHS RANGING FROM
THE LOWER 70S IN THE ARROWHEAD TO AROUND 80 FURTHER SOUTH.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 339 AM CDT SAT AUG 1 2015
OVERALL A SEASONAL PATTERN FOR EARLY AUGUST WITH HIGH TEMPERATURES
PERHAPS ON THE COOL SIDE OF NORMAL FOR A FEW DAYS...A WELCOME RELIEF
TO THE PAST FEW WEEKS WHICH HAVE BEEN WELL ABOVE NORMAL. SOME
CHANCES FOR PRECIPITATION OVER THE MINNESOTA ARROWHEAD MONDAY AND
PERHAPS TUESDAY...BUT OTHERWISE DRY FOR MOST THE NORTHLAND THROUGH
WEDNESDAY. LATER IN THE WEEK MORE WIDESPREAD PRECIP CHANCES...BUT
NOT VERY CONFIDENT GIVEN MODEL VARIABILITY AT THIS TIMEFRAME.
MON/TUES...STACKED LOW MEANDERING OVER HUDSON BAY WILL EVENTUALLY
DRIFT SOUTHEAST INTO NORTHERN ONTARIO...WITH WIDESPREAD WEAK LARGE-
SCALE LIFT AROUND IT THAT MAY RESULT IN A FEW SHOWERS OR STORMS
EDGING INTO FAR NORTHEAST MINNESOTA. THIS THREAT WILL BE HIGHEST ON
MONDAY AFTERNOON WHEN GFS/GEFS/ECMWF ALL DEPICT SOME WEAK LIFT AT
LOW/MID LEVELS AND ENOUGH LOW LEVEL MOISTURE TO RESULT IN A FEW
SHOWERS. OTHERWISE COOL AIR ADVECTING IN FROM THE NORTHWEST WILL
RESULT IN HIGHS AT OR SLIGHTLY BELOW NORMAL...IN THE LOW TO MID 70S.
OVERNIGHT LOWS SUN/MON/TUES NIGHT COULD DIP INTO THE UPPER 40S
ACROSS LOCATIONS AWAY FROM LAKE SUPERIOR DEPENDING ON CLOUD COVER.
WED...A LONGWAVE TROUGH OVER THE NORTHERN HIGH PLAINS DRIFTS
EASTWARD INTO THE UPPER MIDWEST RESULTING IN AT LEAST SOME WEAK WARM
AIR ADVECTION AT LOW LEVELS. INCREASING CLOUDS LATE...DEPENDING ON
HOW UPSTREAM CONVECTION EVOLVES. HIGHS A FEW DEGREES WARMER...BUT
STILL IN THE LOW TO MID 70S RANGE. LOWS WED NIGHT WARMER DUE TO
CLOUD COVER AND WEAK WAA...IN THE LOW TO MID 50S.
THURS/FRI/SAT...A SFC LOW WILL DEVELOP ACROSS THE CENTRAL/NORTHERN
PLAINS IN RESPONSE TO SHORTWAVE TROUGH CROSSING OVER THE NORTHERN
ROCKIES DURING THE MIDDLE OF THE WEEK...BUT HOW IT EVOLVES AS IT
MOVES EAST IS UNCERTAIN. ECMWF...WHICH HAS BEEN A BIT MORE
CONSISTENT RUN-TO-RUN...BRINGS THIS SYSTEM TOWARDS THE UPPER MIDWEST
WHILE THE GFS DEPICTS A COLD FRONT DROPPING SOUTH OUT OF CANADA
RESULTING IN A DRIER SCENARIO FOR THE NORTHLAND AS PRECIP IS FORCED
SOUTH. USED A BLEND OF AVAILABLE GUIDANCE WHICH RESULTED IN SLIGHT
CHANCE TO CHANCE POPS DURING THIS PERIOD. SHOULD THE ECMWF SCENARIO
PLAY OUT IT LOOKS LIKE THIS WILL BE A WIDESPREAD LIGHT TO MODERATE
RAIN EVENT DUE TO LITTLE INSTABILITY ALOFT. TEMPS SEASONABLE IN MOST
SCENERIES...AGAIN IN THE LOW TO MID 70S WITH LOWS MILD IN THE 50S TO
LOW 60S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 636 AM CDT SAT AUG 1 2015
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. INCREASING CLOUDS
LATE TODAY WITH TWO AREAS OF PRECIPITATION EXPECTED OVERNIGHT.
ISOLATED SHOWERS/STORMS WILL ALONG THE INTERNATIONAL BORDER
TOWARDS THE MORNING AND SCATTERED STRONGER STORMS ACROSS EAST
CENTRAL MINNESOTA IN THE EVENING TOWARDS THE OVERNIGHT HOURS.
NEITHER AREA OF PRECIPITATION IS EXPECTED TO REDUCE FLIGHT
CONDITIONS...THOUGH THERE IS A CHANCE FOR IFR CEILINGS TOWARDS THE
MORNING HOURS IF ANY SITES RECEIVE APPRECIABLE RAIN AMOUNTS...BUT
AT THIS POINT THAT LOOKS UNLIKELY.
BREEZY THIS AFTERNOON WITH WEST WINDS OF 10 TO 12 KTS GUSTING TO
NEAR 20 KTS AT TIMES...BECOMING NEAR CALM OVERNIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 81 60 80 55 / 10 40 40 0
INL 79 51 76 50 / 20 50 30 10
BRD 85 58 82 54 / 20 20 20 0
HYR 82 57 81 52 / 10 40 40 0
ASX 81 59 81 55 / 10 40 50 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
UPDATE...MELDE
SHORT TERM...DAP
LONG TERM...JJM
AVIATION...JJM
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
615 AM CDT SAT AUG 1 2015
.SHORT TERM: (THROUGH TONIGHT)
ISSUED AT 340 AM CDT SAT AUG 1 2015
SCATTERED THUNDERSTORMS HAVE RECENTLY DEVELOPED OVER NORTHEAST
MISSOURI AND WEST CENTRAL ILLINOIS IN AN SMALL AREA OF LOW LEVEL
MOISTURE CONVERGENCE. RECENT RUNS OF THE RAP SHOW THIS FORCING
ERODING AROUND 12Z. ATMOSPHERE WILL BECOME UNSTABLE AGAIN THIS
AFTERNOON...HOWEVER THERE WILL BE LITTLE IN THE WAY OF FORCING FOR
IT TO ACT ON. HAVE KEPT CHANCE POPS OVER NORTHEAST MISSOURI AND
WEST CENTRAL ILLINOIS...PARTICULARLY OVERNIGHT AS A SHORTWAVE TROUGH
WILL MOVE THROUGH THE UPPER MIDWEST WHICH WILL LIKELY PUSH A MCS
ALONG A FRONTAL BOUNDARY OVER IOWA INTO INTO THE NORTHERN CWA.
SHOULD BE ANOTHER WARM DAY ACROSS THE AREA WITH 850MB TEMPERATURES
BETWEEN 18-20C. HIGH TEMPERATURES SHOULD CLIMB BACK INTO THE LOW-
MID 90S WITH MIXING UP TO 850MB.
BRITT
.LONG TERM: (SUNDAY THROUGH FRIDAY)
ISSUED AT 340 AM CDT SAT AUG 1 2015
(SUNDAY AND MONDAY)
WILL CONTINUE THE CHANCE OF THUNDERSTORMS ON SUNDAY AS THE COLD
FRONT MOVES DOWN INTO THE AREA. CHANCES WILL BE LOWER ON SUNDAY
NIGHT AND MONDAY AS CONVERGENCE WEAKENS ALONG THE FRONT AS IT MOVES
TO THE SOUTHWEST UNDER NORTHWESTERLY FLOW ALOFT. BOTH DAYS WILL
CONTINUE TO BE WARM WITH MOS TEMPERATURES IN THE LOW-MID 90S AND
850MB TEMPERATURES REMAINING NEAR 20C.
(TUESDAY THROUGH FRIDAY)
IT STILL LOOK LIKE MID TO LATE NEXT WEEK WILL BE UNSETTLED WITH A
CONTINUED CHANCE OF SHOWERS AND THUNDERSTORMS IN NORTHWEST FLOW
ALOFT. BEST CHANCE WILL BE TUESDAY INTO WEDNESDAY WHEN BOTH THE GFS
AND ECMWF SHOW A NOTABLE TROUGH MOVING THROUGH MISSOURI AND
ILLINOIS. TEMPERATURES WILL FALL BACK BELOW NORMAL AS 850MB
TEMPERATURES ARE FORECAST TO BE AROUND 15C.
BRITT
&&
.AVIATION: (FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 610 AM CDT SAT AUG 1 2015
LITTLE CHANGE FROM THE PREV TAFS. CU WITH BASES AROUND 4 TO 5 KFT
ARE EXPECTED TO DEVELOP THIS MORNING AND DISSIPATE THIS EVENING.
WINDS ARE EXPECTED TO BE SWLY AOB 8 KTS. THERE IS A CHANCE FOR
TSRA AT UIN LATE TONIGHT. HOWEVER...HAVE KEPT OUT OF TAF ATTM DUE
TO HIGH UNCERTAINTY IN TIMING WITH BEST CHANCES NEAR THE END OF
THE TAF PERIOD.
TILLY
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
549 AM CDT Sat Aug 1 2015
.SHORT TERM...(Today and Tonight)
Issued at 254 AM CDT SAT AUG 1 2015
It is a fairly quiet morning across the Missouri Ozarks with
mostly clear skies and temperatures rather pleasant in the lower
to middle 60s. Today will be almost a carbon copy of yesterday`s
weather. Temperatures will be in the lower 90s. Humidity values
will still be rather low which means the heat index will be near
the actual air temperature. The latest HiRes short term models
like the HRRR and ARW show a very small potential for a spotty
shower developing this afternoon across the central Missouri area
down into the eastern Ozarks. Not sold on this potential at this
time and will only leave in a silent 10 percent chance for this
happening this afternoon.
.LONG TERM...(Sunday through Friday)
Issued at 254 AM CDT SAT AUG 1 2015
For the end of the weekend into early next week...The upper level
ridge remains west of the region with the center near the west
Texas area and the Missouri Ozarks region will be in a northwest
flow. Southerly winds at the surface will help bring back the
humidity and low level moisture. Temperatures will gradually
increase a degree or two each day with most areas reaching the
lower to middle 90s by Monday. The heat index will climb back into
the upper 90s to around 100 possible.
The weather pattern becomes somewhat unsettled by the middle of
next week. The first of a couple mid level shortwaves will move
across the top of the ridge over the western U.S. early next week.
This shortwave looks fairly decent and will impact the area on
Tuesday afternoon through Wednesday morning. The latest guidance has
moved up the timing a little bit since the previous runs. A weak
frontal boundary also will be stalled out across the Missouri
Ozarks for the middle of next week.
Another impulse will affect the area late Thursday into Friday.
Will not get too specific with timing this far out but it does
appear that there will be several rounds of thunderstorms possible
Tuesday through Friday for the area with a more active weather
pattern likely. Temperatures will also be slightly lower for the
middle and end of next week with highs in the middle to upper 80s.
Overall average rainfall will be in the 1 to 2 inch range for next
week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Sunday Morning)
Issued at 545 AM CDT SAT AUG 1 2015
Mostly clear skies and VFR conditions will continue through
tonight. Surface winds will remain light and variable as high
pressure drifts through the region.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Schaumann
AREA FORECAST DISCUSSION
NWS HASTINGS NE
548 AM CDT SAT AUG 1 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM CDT SAT AUG 1 2015
A FAIRLY CHALLENGING FORECAST THIS MORNING AS CONVECTION HAS
CONTINUED AND ACTUALLY ENHANCED ACROSS PORTIONS OF THE LOCAL
FORECAST AREA OVERNIGHT. WITH THE TRAINING OF THIS CONVECTION OVER
THE SAME AREAS THE PAST FEW HOURS...COULD EVENTUALLY SEE SOME
MINOR FLOODING IN SPOTS IF ADDITIONAL ACTIVITY DEVELOPS.
IN THE MEANTIME...EXPECT AN UPPER LEVEL DISTURBANCE STRETCHING
FROM WESTERN SOUTH DAKOTA ACROSS THE LOCAL FORECAST AREA THIS
MORNING TO CONTINUE TO SPARK SHOWER AND THUNDERSTORM ACTIVITY
ACROSS THE LOCAL AREA THROUGH THE REMAINDER OF THE MORNING HOURS.
WHILE MOST GUIDANCE IS DOING A VERY POOR JOB WITH THE ONGOING
CONVECTION...08Z HRRR SEEMS FAIRLY WELL INITIALIZED...AND HAVE
LEANED TOWARDS THIS SOLUTION IN THE MORNING FORECAST. AS A
RESULT...EXPECT ONGOING CONVECTION TO CONTINUE ACROSS THE
NORTHEASTERN QUADRANT OF THE LOCAL AREA THROUGH THE LATE MORNING
HOURS BEFORE DISSIPATING...WITH THE FOCUS THEN TURNING TO THE
NEXT DISTURBANCE...WHICH IS EXPECTED TO DROP TOWARDS THE LOCAL
AREA FROM SOUTH DAKOTA DURING THE MID TO LATE AFTERNOON HOURS.
WHILE THE COVERAGE AND TIMING FROM THIS DISTURBANCE IS
STILL A BIT UNCERTAIN...SEVERAL MODELS ARE PICKING UP ON THIS
FEATURE...BRINING CONFIDENCE THAT AT LEAST THE NORTHERN PORTIONS
OF THE FORECAST AREA WILL SEE ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS THIS EVENING. WITH CAPE BUILDING AHEAD OF THIS
DISTURBANCE AND AMPLE SHEAR IN PLACE...IN PART DUE TO THE
PRESENCE OF A NEAR STATIONARY FRONTAL BOUNDARY ACROSS THIS
AREA...EXPECT THE POTENTIAL FOR A FEW STRONG TO MARGINALLY SEVERE
STORMS DEVELOPING DURING THE LATE AFTERNOON AND EVENING HOURS.
TEMPERATURE WISE...EXPECT ANOTHER SEASONABLY WARM AFTERNOON ACROSS
THE REGION WITH MOST LOCATIONS THAT ARE ABLE TO CLEAR OUT BY
AFTERNOON EXPECTED TO SEE TEMPERATURES CLIMB INTO THE LOWER TO
MIDDLES 90S...WITH THE BEST CHANCE FOR MORE WIDESPREAD CONVECTION
ALSO EXPECTED DURING THE LATE AFTERNOON THROUGH EARLY EVENING
HOURS. WITH THE RIGHT PARAMETERS IN PLACE...A FEW STRONG TO SEVERE
STORMS APPEAR LIKELY...ESPECIALLY FOR THE NORTHEASTERN PORTIONS OF
THE FORECAST AREA.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 403 AM CDT SAT AUG 1 2015
BIGGEST CONCERNS FOR THE FORECAST PERIOD...CHANCES OF THUNDERSTORMS
MONDAY NIGHT THROUGH TUESDAY NIGHT THEN AGAIN MID WEEK.
MODELS IN RELATIVE AGREEMENT WITH LARGE SCALE FEATURES SO WILL USE
BLEND. GENERALLY IN A NORTHWEST FLOW PATTERN THROUGH THE PERIOD.
THIS TYPE PATTERN TYPICALLY MAKES IT TOUGH TO FORECAST THE SPEED AND
STRENGTH OF SYSTEMS MOVING THROUGH. SO...CONFIDENCE IS NOT THE
HIGHEST IN TIMING...COVERAGE OR EVEN CHANCES OF RAIN UNTIL WE GET 12
TO 24 HOURS AWAY FROM ANY RAIN EVENT.
NONE THE LESS...THE MODELS ARE FAIRLY CONSISTENT IN FORECASTING A
NEARLY STATIONARY BOUNDARY OVER THE FORECAST AREA FROM MONDAY ON.
ALSO...MODELS SUGGEST A SHORT WAVE AND ASSOCIATED JET STREAK WILL
TOP THE RIDGE AND MOVE OVER AN AREA BETWEEN THE DAKOTAS AND KANSAS
ON MONDAY NIGHT OR TUESDAY. THUS...WILL LEAVE CHANCES FOR
THUNDERSTORMS IN FORECAST. IF STORMS DEVELOP THEY APPEAR TO HAVE
ENOUGH INSTABILITY AND WEAK SHEAR THAT A FEW COULD PRODUCE SOME NEAR
SEVERE HAIL STONES AND PERHAPS SOME GUSTY WINDS.
IN BETWEEN ANY STORMS THAT DEVELOP...DRY AND WARM WEATHER IS
EXPECTED. TEMPERATURES SHOULD BE NEAR NORMAL THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z KGRI/KEAR TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 540 AM CDT SAT AUG 1 2015
AN AREA OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO IMPACT THE
TERMINALS DURING THE EARLY MORNING HOURS...ALBEIT WITH HIGH
BASES...CIGS ARE EXPECTED TO REMAIN VFR WITH ONLY TEMPORARY MVFR
VSBYS EXPECTED. OTHERWISE...MID LEVEL CLOUDS WILL LIKELY STREAM
ACROSS THE TERMINALS THROUGH THE AFTERNOON HOURS ACCOMPANIED BY
LIGHT SOUTHERLY BREEZES. ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS WILL THEN BE POSSIBLE DURING THE LATE AFTERNOON OR
EVENING HOURS...BUT DUE TO UNCERTAINTIES IN TIMING AND
COVERAGE...OPTED TO KEEP ONLY A VCTS MENTION FOR THE TIME BEING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...ROSSI
LONG TERM...EDDY
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS ELKO NV
851 AM PDT SAT AUG 1 2015
SYNOPSIS...MONSOON MOISTURE WILL INLFUENCE THE LOCAL REGION.
CENTRAL NEVADA CAN ANTICIPATE THUNDERSTORMS TODAY...WHILE NORTHERN
NEVADA WILL MORE THAN LIKELY BE A SUNDAY EVENT. UNSETTLED WEATHER
EXPECTED THROUGH MIDWEEK.
&&
.UPDATE...INCREASED TEMPERATURES ACROSS NORTHERN NEVADA A COUPLE
OF DEGREES EXPECT HIGH TEMPERATURES IN UPPER 90S IN MANY VALLEY
LOCATIONS TODAY DUE TO STRONG HIGH PRESSURE AND PLENTY OF
AFTERNOON SUNSHINE.
&&
.PREV DISCUSSION... /ISSUED AT 249 AM /
SHORT TERM...TODAY THROUGH SUNDAY. THE SYNOPTIC PATTERN FEATURES
RIDGING TO THE EAST...WITH MOISTURE FLUX INBOUND FROM OUR NEIGHBOR
TO THE SOUTH. THERE IS A WEAK DISTURBANCE EMBEDDED IN THE H5
FLOW...WHICH SHOULD BE THE MAIN EVENT WITH THIS MONSOON EPISODE.
THE NAM AND THE HRRR BOTH DEPICT MOIST AND UNSTABLE AIR IMPACTING
THE LKN CWA THIS FORECAST PERIOD...WITH THE NAM BEING A BIT MORE
BULLISH WITH THE QPF. THE HRRR KICKS INTO GEAR AROUND 18Z SOUTH OF
HIGHWAY 50...WITH MERITED BUMPING UP POPS THIS PACKAGE...WHILE THE
GFS40 IS SLOW TO BRING THE QPF INTO THE LKN CWA TODAY...WHILE THE
NAM SPLITS THE DIFFERENCE. SUNDAY...EXPECT A ANOTHER ROUND OF
QPF...ALBEIT FURTHER NORTH. THE MODELS SEEM TO HAVE SOME MARKET
DIFFERENCES IN THE QPF FIELDS PAST 24 HRS...BUT THE GENERAL TREND
IS A SHIFT TO THE NORTH.
LONG TERM...SUNDAY NIGHT THROUGH SATURDAY. MODELS IN GENERAL
AGREEMENT ON THE BIG PIC THROUGH THE PERIOD...WITH NIGGLING
DIFFERENCES IN THE SMALLER FEATURES PRETTY THROUGHOUT THE LONG TERM.
LOWERS CONFIDENCE IN AN ACCURATE FORECAST...BUT PRECISION IS OKAY
STILL.
UPPER RIDGE MOVES ON EAST AND OPENS THE DOOR FOR MONSOON MOISTURE TO
PERSIST LATE SUNDAY AFTERNOON...BUT THIS SLUG OF MOISTURE WILL MOVE
NORTH IN THE SOUTHWESTERLY DRIER FLOW MOVING INTO THE AREA ATTENDANT
TO THE PACIFIC LOW TRYING TO ABUT THE COASTAL AREAS.
PWS AND INSTABILITY WILL BE SUFFICIENT FOR SHOWERS AND THUNDERSTORMS
OF AN ISOLATED NATURE THROUGH THE EARLIER AND MIDDLE PARTS OF THE
FORECAST RANGE...DWINDLING LATER IN THE PACKAGE. HAVE NOT
DIFFERENTIATED BETWEEN AREAS OF SHOWERS AND THUNDERSTORMS THIS FAR
OUT FOR SIMPLICITY`S SAKE...SO HAVE STAYED TO "TRW" WORDING.
THIS IS A HYBRID SITUATION WITH SOME DRY AND SOME WETTISH
THUNDERSTORMS. MOST STORMS WILL RAIN...AND SOME WILL HAVE BRIEF
HEAVY RAINS.
AVIATION...VFR THROUGH 12Z SUNDAY. INCREASING MOISTURE WILL ENABLE
THUNDERSTORMS AT NEAR KTPH AND KELY SATURDAY AFTERNOON INTO EVENING.
WINDS GENERALLY LIGHT BUT GUSTY AND ERRATIC NEAR STORMS AND VIRGA.
TYPICAL SUMMER PATTER.
FIRE WEATHER...THE LATEST SURFACE ANALYSIS HAS A WELL DEFINED
DOME OF HIGH PRESSURE OVER NM/CO AND A DEEP FETCH OF MOISTURE
RUNNING UP THE SIERRA MADRE OCCIDENTAL AND INTO THE DESERT
SOUTHWEST. EXPECTING THIS MOISTURE TO GRADUALLY WORK ITS WAY INTO
CENTRAL AND NORTHERN NEVADA. BUT BASICALLY ITS KNOCKING ON THE
BACK DOOR OF 457...AND ONCE UNSTABLE...IT SHOULD GET PRETTY
INTERESTING. THE ONLY FLY IN THE OINTMENT WOULD BE IF THE CLOUD
COVERAGE INHIBITS CONVECTIVE INITIATION.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
90/99
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
846 AM PDT SAT AUG 1 2015
.SYNOPSIS...A DISTURBANCE LIFTING NORTHWEST TODAY WILL MOVE ACROSS
THE AREA. THIS IN COMBINATION WITH LINGERING MOISTURE AND
INSTABILITY WILL RESULT IN THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS ESPECIALLY OVER SOUTHERN NEVADA AND NORTHWEST ARIZONA.
ANY STRONGER OR SLOWER MOVING THUNDERSTORMS COULD BE CAPABLE OF
PRODUCING FLASH FLOODING. DRIER AIR WILL WORK INTO THE AREA ON
SUNDAY AND CUT BACK ON THE COVERAGE OF SHOWERS AND THUNDERSTORMS.
GENERALLY DRY CONDITIONS ARE EXPECTED FROM MONDAY ONWARD. HIGH
TEMPERATURES WILL BE WITHIN A FEW DEGREES OF NORMAL NEXT WEEK.
&&
.UPDATE...SEVERAL SMALL SCALE PROCESSES AT WORK THIS MORNING.
DECAYING THUNDERSTORM COMPLEX OVER FAR SOUTHERN MOHAVE COUNTY HAD
PRODUCED AN OUTFLOW BOUNDARY...WITH NEW /BUT WEAK/ STORMS DEVELOPING
IN AN ARC FROM JUST WEST OF VIDAL JUNCTION THROUGH COTTONWOOD COVE
AND /TO A LESSER EXTENT/ EASTWARD TOWARD PEACH SPRINGS. IN
ADDITION...VISIBLE SATELLITE SHOWED A VERY SHARP EDGE TO THE CLOUDS
FROM ROUGHLY TONOPAH TO DESERT ROCK TO WEST OF VIDAL JUNCTION...WITH
CLOUDY SKIES EAST OF THE LINE AND CLEAR SKIES WEST. THIS
DIFFERENTIAL HEATING BOUNDARY WILL LIKELY SERVE AS A FOCUSING
MECHANISM LATER THIS AFTERNOON. FLASH FLOOD WATCH LOOKS GOOD...AND
NO UPDATE PLANNED AT THIS TIME.
&&
.PREV DISCUSSION...
339 AM PDT SAT AUG 1 2015
.SHORT TERM...TONIGHT THROUGH MONDAY NIGHT.
RADAR QUIETED DOWN LAST EVENING NICELY IN OUR AREA, HOWEVER, OUR
BREAK IN THE ACTION WILL NOT LAST LONG AS A NEW DISTURBANCE THAT CAN
BE SEEN ON WATER VAPOR THIS MORNING LIFTING NORTHWEST ACROSS WESTERN
ARIZONA IS ALREADY HELPING TO SPARK SHOWERS AND THUNDERSTORMS OVER
LA PAZ COUNTY. IN ADDITION, SOME WEAKER RETURNS ARE EDGING WEST
ACROSS YAVAPAI AND COCONINO COUNTIES AS WELL. THIS WILL BE THE AREA
TO WATCH THIS MORNING AND ALL OF THE LOCAL ARW AND NMM MODEL RUNS AS
WELL AS THE HRRR AND 00Z OPERATIONAL WRF AND EVEN THE GFS DRIVE
ACTIVITY TOWARD MOHAVE COUNTY BY SUNRISE OR SHORTLY AFTER. THE MAIN
QUESTION IS WHAT STATE IT WILL BE IN AS IT PUSHES ON WEST. THE
THOUGHT, GIVEN THE TIME OF THE MORNING, IS THAT MOST OF IT WILL BE
LIGHT TO MODERATE SHOWERS WITH SOME EMBEDDED HEAVIER THUNDERSTORMS.
LOOKING AHEAD TO THE REST OF TODAY, THIS DISTURBANCE (WITH A
VORTICITY MAXIMUM NOTED AT 500 MB) WILL BE LIFTING NORTHWEST TOWARD
SOUTHERN NEVADA BY THIS EVENING. THE FLOW ALOFT ACROSS THE AREA IS
MAINLY SOUTHEAST TO SOUTH, BUT STARTS TO GO A LITTLE MORE SOUTHWEST
OVER SOCAL. THIS WILL HELP TO PUSH IN DRIER AIR FROM THE SOUTHWEST
AND THE MODELS DO SHOW A DROP IN PWATS OVER WESTERN PARTS OF INYO
AND SAN BERNARDINO COUNTIES. THE LATER WAS VERY QUIET YESTERDAY AND
I SUSPECT TODAY OUTSIDE OF EASTERN PARTS WHERE CONVECTION COULD GET
DRIVEN INTO OUT OF ARIZONA WILL STAY DRY ONCE AGAIN. PWAT VALUES PER
IPW SENSORS CURRENTLY ARE BETWEEN 0.70 AND 1.45 INCH (LOWEST NORTH,
HIGHEST SOUTH) ACROSS THE AREA THIS MORNING AND ACROSS EASTERN AREAS
MAY DROP A LITTLE THIS AFTERNOON BUT NOT MUCH FROM WHAT WE ARE
CURRENTLY SEEING. THUS ONCE AGAIN, THERE WILL BE THE UNLOAD
POTENTIAL IN ANY STRONGER OR SLOWER MOVING THUNDERSTORMS AND THE
FLASH FLOOD WATCH LOOKS GOOD. STORMS TODAY MAY BE DRIVEN MORE BY THE
LIFT FROM THE DISTURBANCE ALOFT BUT ALSO GET A BOOST FROM OLD
OUTFLOW BOUNDARIES IN PLACE, DIFFERENTIAL HEATING BETWEEN CLOUDIER
AND NOT AS CLOUDY AREAS AND TERRAIN. MOST MODELS SHOW QPF ACROSS
CENTRAL NYE COUNTY, BUT HOLD OFF UNTIL THIS AFTERNOON AND EVENING,
THUS THE FLASH FLOOD WATCH WAS EXPANDED TO INCLUDE THIS AREA BUT IT
STARTS LATER AS IT SHOULD REMAIN QUIET THERE UNTIL LATER THIS
MORNING.
ONE CONCERN AGAIN TODAY WITH STORM DEVELOPMENT WILL BE CLOUD COVER
AS THERE IS A LOT OF MID AND HIGH LEVEL CLOUD COVER AROUND AND MORE
MAY EJECT ON IN. IF WE SEE ACTIVITY SPREAD INTO AREAS EARLY ENOUGH,
SUCH AS MOHAVE COUNTY AND EVEN CLARK COUNTY, THEN THESE AREAS MAY
GET WORKED OVER EARLY ENOUGH TO ALSO SEE CONVECTION CUT-OFF EARLIER
THIS EVENING.
COMPLICATING MATTERS TODAY, ESPECIALLY THIS EVENING, IS THE STEERING
FLOW SHOWN ACROSS LINCOLN AND NORTHERN PORTIONS OF CLARK AND MOHAVE
COUNTIES IS OUT OF THE NORTHEAST TO EAST ON THE 00Z OPERATIONAL RUNS
OF THE GFS, WRF AND ECMWF. THIS IS A NOT TOO COMMON SET-UP IN THIS
AREA BUT ONE IN THE PAST THAT HAS RESULTED IN SOME RATHER WHAMMY
STORMS MOVING INTO LAS VEGAS (THE JULY 18, 1994 HILTON SIGN
THUNDERSTORM THE MOST NOTABLE OF ALL BUT ALSO MORE RECENTLY JULY 19,
2013). THERE WAS ALSO AN EVENT ON JULY 11-12, 2008 THAT DID NOT
BRING MUCH WIND BUT SOME VERY INTENSE RAIN IN SPOTS. SEVERAL LOCAL
HIGH RESOLUTION MODEL RUNS OF THE ARW AND NMM SHOW STRONG OUTFLOW
BOUNDARIES DROPPING SOUTH TOWARD CLARK COUNTY OUT OF LINCOLN COUNTY
THIS EVENING. THERE ARE ALSO SOME HINTS OF THIS WITH THE 00Z
OPERATIONAL WRF. CONFIDENCE IN EXACTLY WHAT WILL UNFOLD IS LOW, BUT
GIVEN THE POTENTIAL FOR STORMS TO BE DRIVEN INTO A HIGH DCAPE
ENVIRONMENT (500-1000 J/KG OVER LAS VEGAS, FAVORABLE FOR STRONG
WINDS) FROM THE TERRAIN TO THE NORTH COULD POTENTIALLY TRIGGER
SOMETHING. WE COULD ALSO SEE THINGS NOT PAN OUT. HOWEVER, GIVEN THIS
RARE SET-UP WHICH HAS BEEN A HIGH IMPACT ONE IN THE PAST, THE FLASH
FLOOD WATCH WAS EXTENDED UNTIL 06Z SUNDAY FOR ALL AREAS WHERE IT IS
OUT. SOME MODELS ALSO LINGER CONVECTION ACROSS PARTS OF ESMERALDA
AND CENTRAL/SOUTHERN NYE COUNTIES LATE AS WELL.
TEMPS TODAY WILL BE SEVERAL DEGREES LOWER GIVEN THE CLOUD COVER AND
THUS WE SIDED WITH GUIDANCE FOR HIGHS. LOOK FOR HIGH TEMPS ABOUT 5
DEGREES BELOW NORMAL.
THE DISTURBANCE WILL CONTINUE TO LIFT NORTH ACROSS EASTERN NEVADA
TOMORROW. DRIER AND MORE STABLE AIR IS EXPECTED TO SPREAD NORTHWEST
OVER MORE OF THE AREA AND THIS WILL FURTHER CUT-BACK ON THE COVERAGE
OF SHOWERS AND THUNDERSTORMS. THE AREA TO WATCH WILL BE OVER THE
SOUTHERN SIERRA AS THERE IS A 50 KT+ JET STREAK APPROACHING SOCAL
WHICH MAY AID IN STORM DEVELOPMENT. THE FLOW ALOFT WILL BE
SOUTHWEST, WHICH WILL DRIVE ANY STORMS THAT GO NEAR THE CREST INTO
THE EASTERN SLOPES AND OWENS VALLEY. ALSO WORTH WATCHING WILL BE THE
ADVANCING MOIST-DRY INTERFACE, WHICH MAY HELP TOUCH OFF STORMS. HIGH
TEMPS SHOULD BE 3-5 DEGREES WARMER GIVEN THE EXTRA SUNSHINE AND
LOWER MOISTURE CONTENT (PWATS START TO DROP BELOW AN INCH IN MOST OF
THE AREA).
WITH THE JET STREAK ADVANCING INTO CENTRAL CALIFORNIA ON MONDAY, A
FEW SHOWERS AND THUNDERSTORMS MAY GET GOING AGAIN OVER THE SOUTHERN
SIERRA, OWENS VALLEY AND ESMERALDA COUNTY FROM LINGERING MOISTURE.
OTHERWISE A DRY SOUTHWEST FLOW WILL BE IN PLACE ACROSS THE REST OF
THE AREA. HIGH TEMPS SHOULD BE A FEW DEGREES ABOVE NORMAL AND WE
SIDED WITH THE WARMER END OF GUIDANCE.
.LONG TERM...TUESDAY THROUGH SATURDAY.
DRY SOUTHWEST FLOW WILL BE FIRMLY IN PLACE ACROSS THE CWA
TUESDAY...YIELDING SEASONABLE TEMPERATURES AND BREEZY AFTERNOONS
AREA-WIDE THROUGH THE END OF THE WEEK. DRY CONDITIONS WILL REIGN
ACROSS THE MOJAVE DESERT AND GREAT BASIN THROUGH AT LEAST
THURSDAY...WITH THE EXCEPTION BEING THE SIERRA AND WHITE MOUNTAINS
WHERE THERE MAY BE ENOUGH ENERGY ALOFT AHEAD OF A DEVELOPING UPPER
LOW TO GENERATE A SHOWER OR THUNDERSTORM TUESDAY EVENING.
CONFIDENCE IS INCREASING THIS EVENING IN MOISTURE MAKING A RETURN TO
THE EASTERN ZONES THURSDAY THROUGH THE END OF THE PERIOD AS THE 00Z
OPERATIONAL GFS AND ECMWF ARE MORE IN LINE TONIGHT IN DEVELOPING AN
UPPER LEVEL LOW OFF OF THE COAST OF CALIFORNIA. THEIR ASSOCIATED
ENSEMBLE RUNS GENERALLY HAVE THE SAME IDEA...WITH THE NORMAL
EXPECTED AMOUNT OF DISCREPANCY THIS FAR OUT. WITH THIS FEATURE
PROGGED TO SLOWLY MOVE INLAND...IT WILL AID IN FUNNELING MOISTURE
NORTHWARD OVER MOHAVE COUNTY...AND PERHAPS EASTERN PORTIONS OF
LINCOLN AND CLARK COUNTIES BEFORE MOVING ACROSS AND OUT OF THE AREA.
DECIDED TO INCREASE POPS ACROSS MAINLY MOHAVE COUNTY THURSDAY
THROUGH SATURDAY TO ALLOW FOR A MENTION OF THUNDERSTORMS AS A
RESULT. ASIDE FROM INCREASED STORM CHANCES...THIS SYSTEM WILL BRING
AN INCREASE IN AFTERNOON WINDS ACROSS THE MOJAVE DESERT AND SOUTHERN
GREAT BASIN NEXT WEEKEND AS IT TRAVERSES THE AREA.
DESPITE EXCELLENT MODEL AGREEMENT TONIGHT...THIS FEATURE WILL BE
MONITORED CLOSELY IN THE COMING DAYS FOR CONSISTENCY...AS CHANGES IN
THE DEVELOPMENT AND POSITIONING OF KEY FEATURES WILL AFFECT THE
RESULTANT WEATHER LATER NEXT WEEK.
.AVIATION...FOR MCCARRAN...THE MAIN CHALLENGE THROUGH TONIGHT WILL
BE THE TIMING OF ANY SHRA/TSRA AS WELL AS ANY OUTFLOW BOUNDARIES
THAT THEY MAY TRIGGER. THE POTENTIAL FOR SHRA/TSRA WILL INCREASE
BETWEEN 12Z AND 15Z TODAY AS ACTIVITY MAY MOVE NORTHWEST TOWARD LAS
VEGAS FROM ARIZONA. ADDITIONAL SHRA/TSRA ACTIVITY MAY DEVELOP IN AND
AROUND THE VALLEY FROM LATER THIS MORNING INTO THIS EVENING. SOME
MODELS ALSO INDICATE THE POTENTIAL FOR SHRA/TSRA OR OUTFLOW TO WORK
IN LATER THIS EVENING FROM THE NORTH TO NORTHEAST. AWAY FROM
SHRA/TSRA OR OUTFLOW BOUNDARIES WINDS SHOULD TREND TOWARD DIURNAL
DIRECTIONS AT 5-10 KTS. MAINLY BKN CIGS AOA 10K-15K FEET WITH BASES
LOWERING BELOW 8K FEET IN AND NEAR ANY SHRA/TSRA. MOUNTAIN
OBSCURATIONS ARE POSSIBLE.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...CONFIDENCE IN THE EXACT TIMING OF SHRA/TSRA IS LOW
THROUGH TONIGHT SO WILL TRY TO BASE TAF TIMING ON RADAR AND HI-
RESOLUTION MODEL TRENDS IN EARLIER PERIODS AND ADJUST AS NEED BE.
OVERALL THE BEST CHANCE FOR SHRA/TSRA WILL BE EAST OF A LINE FROM
KIYK-KEED-KHII. GUSTY AND ERRATIC WINDS AND VSBY AND CIGS REDUCED TO
MVFR OR LOWER ARE POSSIBLE IN AND NEAR ANY SHRA/TSRA THROUGH
TONIGHT. ACTIVITY MAY LINGER LONGER TONIGHT, ESPECIALLY IN SOUTHERN
NEVADA, POTENTIALLY GOING UNTIL CLOSER TO 06Z SUNDAY. OTHERWISE,
EXPECT WINDS TO TREND TOWARD TYPICAL DIURNAL DIRECTIONS AT 6-12 KTS
WITH MAINLY BKN CLOUDS AOA 10K-15K FEET EXCEPT AROUND KDAG WHERE
THEY WILL BE MORE 20-25K FEET IN THE SCT-BKN RANGE.
.SPOTTER INFORMATION STATEMENT...SPOTTERS ARE ENCOURAGED TO REPORT
ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING
PROCEDURES THROUGH SUNDAY. THE REMAINDER OF THE WEEK LOOKS DRY.
&&
$$
UPDATE...MORGAN
SHORT TERM/AVIATION...STACHELSKI
LONG TERM...PULLIN
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
339 AM PDT SAT AUG 1 2015
.SYNOPSIS...A DISTURBANCE LIFTING NORTHWEST TODAY WILL MOVE ACROSS
THE AREA. THIS IN COMBINATION WITH LINGERING MOISTURE AND
INSTABILITY WILL RESULT IN THE POTENTIAL FOR SHOWERS AND
THUNDERSTORMS ESPECIALLY OVER SOUTHERN NEVADA AND NORTHWEST ARIZONA.
ANY STRONGER OR SLOWER MOVING THUNDERSTORMS COULD BE CAPABLE OF
PRODUCING FLASH FLOODING. DRIER AIR WILL WORK INTO THE AREA ON
SUNDAY AND CUT BACK ON THE COVERAGE OF SHOWERS AND THUNDERSTORMS.
GENERALLY DRY CONDITIONS ARE EXPECTED FROM MONDAY ONWARD. HIGH
TEMPERATURES WILL BE WITHIN A FEW DEGREES OF NORMAL NEXT WEEK.
&&
.SHORT TERM...TONIGHT THROUGH MONDAY NIGHT.
RADAR QUIETED DOWN LAST EVENING NICELY IN OUR AREA, HOWEVER, OUR
BREAK IN THE ACTION WILL NOT LAST LONG AS A NEW DISTURBANCE THAT CAN
BE SEEN ON WATER VAPOR THIS MORNING LIFTING NORTHWEST ACROSS WESTERN
ARIZONA IS ALREADY HELPING TO SPARK SHOWERS AND THUNDERSTORMS OVER
LA PAZ COUNTY. IN ADDITION, SOME WEAKER RETURNS ARE EDGING WEST
ACROSS YAVAPAI AND COCONINO COUNTIES AS WELL. THIS WILL BE THE AREA
TO WATCH THIS MORNING AND ALL OF THE LOCAL ARW AND NMM MODEL RUNS AS
WELL AS THE HRRR AND 00Z OPERATIONAL WRF AND EVEN THE GFS DRIVE
ACTIVITY TOWARD MOHAVE COUNTY BY SUNRISE OR SHORTLY AFTER. THE MAIN
QUESTION IS WHAT STATE IT WILL BE IN AS IT PUSHES ON WEST. THE
THOUGHT, GIVEN THE TIME OF THE MORNING, IS THAT MOST OF IT WILL BE
LIGHT TO MODERATE SHOWERS WITH SOME EMBEDDED HEAVIER THUNDERSTORMS.
LOOKING AHEAD TO THE REST OF TODAY, THIS DISTURBANCE (WITH A
VORTICITY MAXIMUM NOTED AT 500 MB) WILL BE LIFTING NORTHWEST TOWARD
SOUTHERN NEVADA BY THIS EVENING. THE FLOW ALOFT ACROSS THE AREA IS
MAINLY SOUTHEAST TO SOUTH, BUT STARTS TO GO A LITTLE MORE SOUTHWEST
OVER SOCAL. THIS WILL HELP TO PUSH IN DRIER AIR FROM THE SOUTHWEST
AND THE MODELS DO SHOW A DROP IN PWATS OVER WESTERN PARTS OF INYO
AND SAN BERNARDINO COUNTIES. THE LATER WAS VERY QUIET YESTERDAY AND
I SUSPECT TODAY OUTSIDE OF EASTERN PARTS WHERE CONVECTION COULD GET
DRIVEN INTO OUT OF ARIZONA WILL STAY DRY ONCE AGAIN. PWAT VALUES PER
IPW SENSORS CURRENTLY ARE BETWEEN 0.70 AND 1.45 INCH (LOWEST NORTH,
HIGHEST SOUTH) ACROSS THE AREA THIS MORNING AND ACROSS EASTERN AREAS
MAY DROP A LITTLE THIS AFTERNOON BUT NOT MUCH FROM WHAT WE ARE
CURRENTLY SEEING. THUS ONCE AGAIN, THERE WILL BE THE UNLOAD
POTENTIAL IN ANY STRONGER OR SLOWER MOVING THUNDERSTORMS AND THE
FLASH FLOOD WATCH LOOKS GOOD. STORMS TODAY MAY BE DRIVEN MORE BY THE
LIFT FROM THE DISTURBANCE ALOFT BUT ALSO GET A BOOST FROM OLD
OUTFLOW BOUNDARIES IN PLACE, DIFFERENTIAL HEATING BETWEEN CLOUDIER
AND NOT AS CLOUDY AREAS AND TERRAIN. MOST MODELS SHOW QPF ACROSS
CENTRAL NYE COUNTY, BUT HOLD OFF UNTIL THIS AFTERNOON AND EVENING,
THUS THE FLASH FLOOD WATCH WAS EXPANDED TO INCLUDE THIS AREA BUT IT
STARTS LATER AS IT SHOULD REMAIN QUIET THERE UNTIL LATER THIS
MORNING.
ONE CONCERN AGAIN TODAY WITH STORM DEVELOPMENT WILL BE CLOUD COVER
AS THERE IS A LOT OF MID AND HIGH LEVEL CLOUD COVER AROUND AND MORE
MAY EJECT ON IN. IF WE SEE ACTIVITY SPREAD INTO AREAS EARLY ENOUGH,
SUCH AS MOHAVE COUNTY AND EVEN CLARK COUNTY, THEN THESE AREAS MAY
GET WORKED OVER EARLY ENOUGH TO ALSO SEE CONVECTION CUT-OFF EARLIER
THIS EVENING.
COMPLICATING MATTERS TODAY, ESPECIALLY THIS EVENING, IS THE STEERING
FLOW SHOWN ACROSS LINCOLN AND NORTHERN PORTIONS OF CLARK AND MOHAVE
COUNTIES IS OUT OF THE NORTHEAST TO EAST ON THE 00Z OPERATIONAL RUNS
OF THE GFS, WRF AND ECMWF. THIS IS A NOT TOO COMMON SET-UP IN THIS
AREA BUT ONE IN THE PAST THAT HAS RESULTED IN SOME RATHER WHAMMY
STORMS MOVING INTO LAS VEGAS (THE JULY 18, 1994 HILTON SIGN
THUNDERSTORM THE MOST NOTABLE OF ALL BUT ALSO MORE RECENTLY JULY 19,
2013). THERE WAS ALSO AN EVENT ON JULY 11-12, 2008 THAT DID NOT
BRING MUCH WIND BUT SOME VERY INTENSE RAIN IN SPOTS. SEVERAL LOCAL
HIGH RESOLUTION MODEL RUNS OF THE ARW AND NMM SHOW STRONG OUTFLOW
BOUNDARIES DROPPING SOUTH TOWARD CLARK COUNTY OUT OF LINCOLN COUNTY
THIS EVENING. THERE ARE ALSO SOME HINTS OF THIS WITH THE 00Z
OPERATIONAL WRF. CONFIDENCE IN EXACTLY WHAT WILL UNFOLD IS LOW, BUT
GIVEN THE POTENTIAL FOR STORMS TO BE DRIVEN INTO A HIGH DCAPE
ENVIRONMENT (500-1000 J/KG OVER LAS VEGAS, FAVORABLE FOR STRONG
WINDS) FROM THE TERRAIN TO THE NORTH COULD POTENTIALLY TRIGGER
SOMETHING. WE COULD ALSO SEE THINGS NOT PAN OUT. HOWEVER, GIVEN THIS
RARE SET-UP WHICH HAS BEEN A HIGH IMPACT ONE IN THE PAST, THE FLASH
FLOOD WATCH WAS EXTENDED UNTIL 06Z SUNDAY FOR ALL AREAS WHERE IT IS
OUT. SOME MODELS ALSO LINGER CONVECTION ACROSS PARTS OF ESMERALDA
AND CENTRAL/SOUTHERN NYE COUNTIES LATE AS WELL.
TEMPS TODAY WILL BE SEVERAL DEGREES LOWER GIVEN THE CLOUD COVER AND
THUS WE SIDED WITH GUIDANCE FOR HIGHS. LOOK FOR HIGH TEMPS ABOUT 5
DEGREES BELOW NORMAL.
THE DISTURBANCE WILL CONTINUE TO LIFT NORTH ACROSS EASTERN NEVADA
TOMORROW. DRIER AND MORE STABLE AIR IS EXPECTED TO SPREAD NORTHWEST
OVER MORE OF THE AREA AND THIS WILL FURTHER CUT-BACK ON THE COVERAGE
OF SHOWERS AND THUNDERSTORMS. THE AREA TO WATCH WILL BE OVER THE
SOUTHERN SIERRA AS THERE IS A 50 KT+ JET STREAK APPROACHING SOCAL
WHICH MAY AID IN STORM DEVELOPMENT. THE FLOW ALOFT WILL BE
SOUTHWEST, WHICH WILL DRIVE ANY STORMS THAT GO NEAR THE CREST INTO
THE EASTERN SLOPES AND OWENS VALLEY. ALSO WORTH WATCHING WILL BE THE
ADVANCING MOIST-DRY INTERFACE, WHICH MAY HELP TOUCH OFF STORMS. HIGH
TEMPS SHOULD BE 3-5 DEGREES WARMER GIVEN THE EXTRA SUNSHINE AND
LOWER MOISTURE CONTENT (PWATS START TO DROP BELOW AN INCH IN MOST OF
THE AREA).
WITH THE JET STREAK ADVANCING INTO CENTRAL CALIFORNIA ON MONDAY, A
FEW SHOWERS AND THUNDERSTORMS MAY GET GOING AGAIN OVER THE SOUTHERN
SIERRA, OWENS VALLEY AND ESMERALDA COUNTY FROM LINGERING MOISTURE.
OTHERWISE A DRY SOUTHWEST FLOW WILL BE IN PLACE ACROSS THE REST OF
THE AREA. HIGH TEMPS SHOULD BE A FEW DEGREES ABOVE NORMAL AND WE
SIDED WITH THE WARMER END OF GUIDANCE.
.LONG TERM...TUESDAY THROUGH SATURDAY.
DRY SOUTHWEST FLOW WILL BE FIRMLY IN PLACE ACROSS THE CWA
TUESDAY...YIELDING SEASONABLE TEMPERATURES AND BREEZY AFTERNOONS
AREA-WIDE THROUGH THE END OF THE WEEK. DRY CONDITIONS WILL REIGN
ACROSS THE MOJAVE DESERT AND GREAT BASIN THROUGH AT LEAST
THURSDAY...WITH THE EXCEPTION BEING THE SIERRA AND WHITE MOUNTAINS
WHERE THERE MAY BE ENOUGH ENERGY ALOFT AHEAD OF A DEVELOPING UPPER
LOW TO GENERATE A SHOWER OR THUNDERSTORM TUESDAY EVENING.
CONFIDENCE IS INCREASING THIS EVENING IN MOISTURE MAKING A RETURN TO
THE EASTERN ZONES THURSDAY THROUGH THE END OF THE PERIOD AS THE 00Z
OPERATIONAL GFS AND ECMWF ARE MORE IN LINE TONIGHT IN DEVELOPING AN
UPPER LEVEL LOW OFF OF THE COAST OF CALIFORNIA. THEIR ASSOCIATED
ENSEMBLE RUNS GENERALLY HAVE THE SAME IDEA...WITH THE NORMAL
EXPECTED AMOUNT OF DISCREPANCY THIS FAR OUT. WITH THIS FEATURE
PROGGED TO SLOWLY MOVE INLAND...IT WILL AID IN FUNNELING MOISTURE
NORTHWARD OVER MOHAVE COUNTY...AND PERHAPS EASTERN PORTIONS OF
LINCOLN AND CLARK COUNTIES BEFORE MOVING ACROSS AND OUT OF THE AREA.
DECIDED TO INCREASE POPS ACROSS MAINLY MOHAVE COUNTY THURSDAY
THROUGH SATURDAY TO ALLOW FOR A MENTION OF THUNDERSTORMS AS A
RESULT. ASIDE FROM INCREASED STORM CHANCES...THIS SYSTEM WILL BRING
AN INCREASE IN AFTERNOON WINDS ACROSS THE MOJAVE DESERT AND SOUTHERN
GREAT BASIN NEXT WEEKEND AS IT TRAVERSES THE AREA.
DESPITE EXCELLENT MODEL AGREEMENT TONIGHT...THIS FEATURE WILL BE
MONITORED CLOSELY IN THE COMING DAYS FOR CONSISTENCY...AS CHANGES IN
THE DEVELOPMENT AND POSITIONING OF KEY FEATURES WILL AFFECT THE
RESULTANT WEATHER LATER NEXT WEEK.
&&
.AVIATION...FOR MCCARRAN...THE MAIN CHALLENGE THROUGH TONIGHT WILL
BE THE TIMING OF ANY SHRA/TSRA AS WELL AS ANY OUTFLOW BOUNDARIES
THAT THEY MAY TRIGGER. THE POTENTIAL FOR SHRA/TSRA WILL INCREASE
BETWEEN 12Z AND 15Z TODAY AS ACTIVITY MAY MOVE NORTHWEST TOWARD LAS
VEGAS FROM ARIZONA. ADDITIONAL SHRA/TSRA ACTIVITY MAY DEVELOP IN AND
AROUND THE VALLEY FROM LATER THIS MORNING INTO THIS EVENING. SOME
MODELS ALSO INDICATE THE POTENTIAL FOR SHRA/TSRA OR OUTFLOW TO WORK
IN LATER THIS EVENING FROM THE NORTH TO NORTHEAST. AWAY FROM
SHRA/TSRA OR OUTFLOW BOUNDARIES WINDS SHOULD TREND TOWARD DIURNAL
DIRECTIONS AT 5-10 KTS. MAINLY BKN CIGS AOA 10K-15K FEET WITH BASES
LOWERING BELOW 8K FEET IN AND NEAR ANY SHRA/TSRA. MOUNTAIN
OBSCURATIONS ARE POSSIBLE.
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...CONFIDENCE IN THE EXACT TIMING OF SHRA/TSRA IS LOW
THROUGH TONIGHT SO WILL TRY TO BASE TAF TIMING ON RADAR AND HI-
RESOLUTION MODEL TRENDS IN EARLIER PERIODS AND ADJUST AS NEED BE.
OVERALL THE BEST CHANCE FOR SHRA/TSRA WILL BE EAST OF A LINE FROM
KIYK-KEED-KHII. GUSTY AND ERRATIC WINDS AND VSBY AND CIGS REDUCED TO
MVFR OR LOWER ARE POSSIBLE IN AND NEAR ANY SHRA/TSRA THROUGH
TONIGHT. ACTIVITY MAY LINGER LONGER TONIGHT, ESPECIALLY IN SOUTHERN
NEVADA, POTENTIALLY GOING UNTIL CLOSER TO 06Z SUNDAY. OTHERWISE,
EXPECT WINDS TO TREND TOWARD TYPICAL DIURNAL DIRECTIONS AT 6-12 KTS
WITH MAINLY BKN CLOUDS AOA 10K-15K FEET EXCEPT AROUND KDAG WHERE
THEY WILL BE MORE 20-25K FEET IN THE SCT-BKN RANGE.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTERS ARE ENCOURAGED TO REPORT
ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING
PROCEDURES THROUGH SUNDAY. THE REMAINDER OF THE WEEK LOOKS DRY.
&&
$$
SHORT TERM/AVIATION...STACHELSKI
LONG TERM...PULLIN
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
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AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
928 AM EDT SAT AUG 1 2015
.SYNOPSIS...
A STATIONARY FRONT ALONG THE SOUTHEAST COAST WILL DISSIPATE EARLY
NEXT WEEK. A COLD FRONT WILL APPROACH FROM THE NORTHWEST LATE IN
THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 930 AM SATURDAY...BULK OF RAINFALL IS OFFSHORE AND LATEST
HIGH-RESOLUTION MODELS...INCLUDING THE HRRR AND RAP...SHOW RAIN
SHOULD GENERALLY REMAIN OFFSHORE TODAY. HAVE TWEAKED POPS DOWN
OVER LAND FOR THE BALANCE OF THE DAY. NO CHANGES TO CURRENT
TEMPERATURE FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
AS OF 330 AM SAT...LITTLE IF ANY CHANGE IN SYNOPTIC PATTERN. WILL
CARRY SLIGHT CHANCE POPS IMMEDIATE SOUTH COAST AND SOUTHERN OUTER
BANKS IN THE EVENING...THEN LIMITED POPS TO CENTRAL AND SOUTHERN
COASTAL WATERS. WARM AND MUGGY OVERNIGHT WITH LOWS AROUND 70
COASTAL PLAIN TO MID/UPPER 70S OUTER BANKS.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
AS OF 4 AM SAT...THE STATIONARY FRONT WILL DISSIPATE SUNDAY WITH
BROAD TROUGHING ALOFT CONTINUING THROUGH EARLY NEXT WEEK WITH
MAINLY DRY CONDITIONS. ANOTHER COLD FRONT WILL PUSH INTO THE
REGION BY LATE WEEK WITH BETTER CHANCES FOR THUNDERSHOWERS.
SUNDAY...THE MODELS CONTINUE THE MAINLY DRY TREND FOR SUNDAY AND
HAVE MAINTAINED GENERALLY 20 POPS FOR THE AREA WITH JUST AN ISO
THUNDERSHOWER AS SEA BREEZE BOUNDARY PROPAGATES INLAND THROUGH THE
AFTERNOON. HIGHS COULD BE A BIT WARMER WITH LOW/MID 90S INLAND TO
80S COAST. ANY SHOWERS/STORMS WILL DIMINISH WITH LOSS OF HEATING
INLAND THOUGH MAINTAINED SMALL POPS COASTAL AREAS WHERE ELEVATED
INSTABILITY WILL REMAIN THROUGH THE OVERNIGHT.
MONDAY THROUGH WEDNESDAY...WARMING TEMPS EXPECTED AS HEIGHTS AND
850 MB TEMPS RISE SOMEWHAT. SSW WINDS WILL INCREASE WITH GUSTY
WINDS DURING THE AFTERNOON HOURS. HIGHS WILL BE AS HIGH AS THE MID
90S INLAND...THOUGH AT THIS TIME NOT EXPECTING HEAT ADV CRITERIA
TO BE MET WITH GENERALLY LOW 100S EXPECTED EACH AFTERNOON AS TD`S
WILL BE IN THE 60S WHERE HOTTEST TEMPS OCCUR. MORE TYPICAL
SUMMERY PATTERN WITH RESPECT TO PRECIP CHANCES...ISO TO SCT
AFTERNOON CONVECTION DURING THE AFTERNOON HOURS AWAY FROM THE
COAST. ELEVATED INSTABILITY WILL POOL TO THE SOUTH OF THE AREA AND
THEREFORE KEPT 20-30 POPS COASTAL AREAS FOR THE THREAT OF ELEVATED
THUNDER EACH NIGHT. 01-00Z ECM/CMC BRING SFC FRONT INTO THE MID
ATLANTIC AS EARLY AS WEDNESDAY...WHICH WOULD BE A FOCUS FOR A
BETTER CHANCE OF THUNDERSTORMS...THOUGH AT THIS TIME WILL MAINTAIN
ONLY 20 POPS.
THURSDAY AND FRIDAY...BETTER CHANCE OF STORMS LOOKS TO BE THURSDAY
INTO FRIDAY...AS DETERMINISTIC GFS/ECM ALONG WITH THEIR ENSEMBLE
MEAN BRINGS SHORTWAVE ENERGY WITH DECREASING HEIGHTS INTO THE
MID ATLANTIC/SOUTHEAST CONUS. ECMWF IS A DAY FASTER THAN THE
GFS...SO WILL ONLY HIGHLIGHT 30-40 POPS FOR THIS TIME PERIOD.
ECMWF DYNAMICS WOULD SUPPORT AN ORGANIZED THREAT FOR STORMS WITH
25-30 KT OF DEEP SHEAR IN PLACE...THOUGH AT THIS LONG RANGE AND
MODEL DISAGREEMENT WILL NOT HIGHLIGHT A THREAT FOR SEVERE IN HWO
QUITE YET. TEMPS WILL BE A BIT MORE TOLERABLE WITH THE INCREASED
CLOUDS AND PRECIP...WITH HIGHS AROUND 90.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH TONIGHT/
AS OF 7 AM SAT...PATCHY IFR/MVFR VSBYS WILL BURN OFF IN NEXT HOUR
OR SO AS SUN COMES UP. ISOLATED AFTERNOON/EVENING CONVECTION
POSSIBLE AT TERMINALS EWN AND OAJ...DRY FORECAST FOR PGV AND ISO.
SOUTH WINDS AROUND 5 KNOTS DURING THE DAY...CALM TO LIGHT AND
VARIABLE OTHERWISE. MVFR CIGS/VSBYS POSSIBLE AGAIN IN THE PREDAWN
HOURS OF SUNDAY MORNING.
LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 4 AM SAT...PRED VFR CONDITIONS EXPECTED THROUGH THE PERIOD.
A WEAK FRONT WILL DISSIPATE WITH ONLY ISO STORMS EXPECTED EACH
AFTERNOON. PATCHY FOG/STRATUS POSSIBLE EACH NIGHT WITH MOIST BL
AND LIGHT WINDS...ESP FOR AREAS THAT RECEIVE RAINFALL. SW WINDS
MAY BECOME GUSTY TUE AND WED AFTERNOONS AS THERMAL TROUGH DEEPENS
ACROSS THE CAROLINA PIEDMONT.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/
AS OF 930 AM SATURDAY...WINDS ARE RATHER CONFUSED ACROSS THE
REGION THIS MORNING WITH WAVY FRONTAL BOUNDARY BISECTING THE AREA.
WINDS SHOULD GRADUALLY BECOME S/SW BY LATE THIS EVENING AND
TONIGHT. WINDS SPEEDS WILL REMAIN AT 15 KNOTS OR LESS WITH SEAS 2
TO 4 FEET TODAY INTO TONIGHT. THE FRONT WILL SLIP OFFSHORE AGAIN
BY EARLY SUNDAY MORNING WITH WINDS BECOMING MORE W/NW.
LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 4 AM SAT...EXPECT PRED S/SW FLOW THROUGH MOST OF THE
PERIOD. GRADIENT TIGHTENS THROUGH THE DAY SUN WITH INCREASING SSW
WINDS 10-20KT LATE SUN. A PERIOD OF OCCASIONAL MARGINAL SCA
CONDITIONS POSSIBLE SUN NIGHT THROUGH WEDNESDAY AS SSW WINDS
INCREASE TO 15-20 KT WITH HIGHER GUSTS AND SEAS BUILDING 4 TO 6
FEET. A COLD FRONT WILL APPROACH THE AREA BY THURSDAY WITH WINDS
AND SEAS DIMINISHING SOMEWHAT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HSA
NEAR TERM...CTC
SHORT TERM...HSA
LONG TERM...TL
AVIATION...HSA/TL
MARINE...CTC/TL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
931 AM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 926 AM CDT SAT AUG 1 2015
OTHER THAN TO BLEND TO OBSERVED TRENDS THROUGH 14 UTC...THE
ONGOING FORECAST IS ON TRACK WITH A HOT DAY EXPECTED IN THE WARM
SECTOR OF A WEAK SURFACE LOW ACROSS WESTERN NORTH DAKOTA THIS
AFTERNOON. DID MAINTAIN AN ISOLATED TO SCATTERED MENTION OF
THUNDERSTORMS ACROSS THE FAR SOUTHERN JAMES RIVER VALLEY AS
SUPPORTED BY THE 06 AND INCOMING 12 UTC GLOBAL GUIDANCE AND 12-13
UTC HRRR ITERATIONS WHERE LOWER 60S DEWPOINTS ARE EXPECTED TO
REMAIN THIS AFTERNOON.
UPDATE ISSUED AT 616 AM CDT SAT AUG 1 2015
AREA OF CLOUDS WITH A FEW SPRINKLES IN WEAK THETA-E ADVECTION OVER
CENTRAL ND INTO THE JAMES RIVER VALLEY CONTINUE TO SLOWLY SHIFT
TO THE EAST. FOR EARLY MORNING UPDATE WILL ADJUST CLOUD COVER AND
ADD MENTION OF SPRINKLES...ENDING BY MID MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CDT SAT AUG 1 2015
A VERY WARM DAY TODAY HIGHLIGHTS THE SHORT TERM FORECAST.
NORTHWEST UPPER LEVEL JET FLOW CONTINUED OVER THE STATE...WITH
AN UPPER LEVEL LOW OVER HUDSON BAY AND A WARM WESTERN RIDGE OVER THE
WEST COAST AND ROCKIES. WARM AND DRY AIR WAS SOUTHWEST OF THE UPPER
LEVEL JET WITH COOLER AIR TO THE NORTHEAST.
EARLY THIS MORNING ISOLATED SHOWERS DEVELOPED...LIKELY ALONG A
BOUNDARY BETWEEN A SOUTHERLY LOW LEVEL JET ALONG WESTERN NEBRASKA
INTO THE WESTERN DAKOTAS. ENOUGH LIFT WAS OCCURRING IN A NORTHWEST-
TO-SOUTHEAST FASHION ACROSS CENTRAL NORTH DAKOTA. THE LATEST
ITERATION OF THE HRRR INDICATES THE AREA OF ISOLATED SHOWERS
SHIFTING EAST TO THE JAMES VALLEY BEFORE SUNRISE...THEN CONTINUING
EAST OUT OF THE JAMES VALLEY.
A COLD FRONT OVER THE CENTRAL CANADIAN PRAIRIE PROVINCES THIS
MORNING IS FORECAST TO MOVE SOUTH TODAY AND ENTER NORTHWESTERN NORTH
DAKOTA BY THIS EVENING...SWEEPING SOUTHEAST ACROSS THE STATE
TONIGHT. LOOK FOR A VERY WARM DAY TODAY AHEAD OF THE FRONT. WESTERLY
MIXING WINDS ALOFT SHOULD INCREASE WITH THE APPROACH OF THE FRONT
DUE TO THE INCREASING PRESSURE GRADIENT. FORECAST SOUNDINGS INDICATE
AN ADIABATIC LINK FROM THE SURFACE UP TO AROUND H700 THIS AFTERNOON.
WENT ABOVE GUIDANCE FOR MAX TEMPS AND RAISED WINDS A BIT AS WELL
FROM GUIDANCE. LOOKING AT HIGHS TODAY IN THE LOW TO MID 90S OVER
MOST OF WESTERN AND CENTRAL NORTH DAKOTA.
TONIGHT AS THE COLD FRONT SWEEPS SOUTHEAST ACROSS THE STATE...THE
BEST UPPER LEVEL FORCING RESIDES TO OUR NORTHEAST IN THE FLOW OF THE
UPPER JET - WHICH SHOULD HAVE LIFTED NORTHEAST DURING THE DAY
ALLOWING THE VERY WARM AND DRY AIR TO ADVANCE INTO CENTRAL NORTH
DAKOTA. HAVE KEPT THE SLIGHT CHANCES OF THUNDERSTORMS ACROSS THE
TURTLE MOUNTAIN AREA. COOLER AIR MOVES INTO THE STATE TONIGHT WITH
NORTHWEST WINDS BEHIND THE COLD FRONT. KEPT LOWS TONIGHT IN THE 50S
AS THE NORTHWEST WINDS WILL KEEP THE LOWER ATMOSPHERE MIXED ENOUGH
SO THAT TEMPS DO NOT DROP INTO THE 40S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 301 AM CDT SAT AUG 1 2015
COOLER TEMPERATURES EXPECTED OVER THE AREA ON SUNDAY IN THE WAKE
OF THE COLD FRONT. OTHERWISE...DRY CONDITIONS EXPECTED WITH UPPER
RIDGE AXIS SLIDING OVER THE ROCKIES AND SURFACE HIGH SETTLING OVER
THE REGION. DRY WEATHER CONTINUES INTO MONDAY WITH RIDGE AXIS
PUSHING TOWARDS THE NORTHERN PLAINS.
ACTIVE WEATHER PATTERN EXPECTED TOWARDS MID-WEEK WITH RIDGE
BREAKING DOWN AND A VARIETY OF SHORT WAVES EJECTING OVER THE AREA
FROM A BROAD UPPER LOW OVER BRITISH COLUMBIA. UNSETTLED PATTERN
CONTINUES INTO THE END OF THE WEEK AS LOW STARTS TO MAKE ITS WAY
EASTERLY. BELOW AVERAGE TEMPERATURES EXPECTED THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 926 AM CDT SAT AUG 1 2015
VFR CONDITIONS WILL CONTINUE THROUGH THE FORECAST PERIOD. LIGHT
WINDS SHOULD BECOME SOUTHERLY OR SOUTHWESTERLY AHEAD OF A COLD FRONT
THAT IS FORECAST TO MOVE THROUGH KISN AROUND 00Z...AND THROUGH KMOT
AND KDIK AROUND 04Z SATURDAY EVENING...REACHING KJMS AROUND 09Z.
SOUTHWEST WINDS COULD BE GUSTY AT TIMES AT KISN AND KDIK THIS
AFTERNOON BETWEEN 17Z AND 00Z. ISOLATED THUNDERSTORMS ARE POSSIBLE
SOUTH OF KJMS THIS AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 301 AM CDT SAT AUG 1 2015
AN ADIABATIC LAPSE RATE UP TO H700 THIS AFTERNOON WILL ALLOW
MIXING WINDS ALOFT TO LINK WITH THE SURFACE. EXPECTING 15 TO 20
MPH WINDS FOR A TIME THIS AFTERNOON IN THE WEST AS TEMPERATURES
REACH INTO THE 90S. DEWPOINTS IN THE 40S OVER SOUTHWESTERN NORTH
DAKOTA THIS MORNING ARE EXPECTED TO DROP INTO THE 30S THIS
AFTERNOON AS THE LOWER ATMOSPHERE MIXES WITH MID LEVELS.
TEMPERATURES IN THE MID 90S WITH DEWPOINTS IN THE 30S SHOULD
RESULT IN MINIMUM RELATIVE HUMIDITY VALUES IN THE 10 TO 15 PERCENT
RANGE OVER MUCH OF WESTERN NORTH DAKOTA...MAINLY ALONG AND WEST OF
A LINE FROM WILLISTON TO WATFORD CITY TO DICKINSON AND HETTINGER.
IN ADDITION...WINDS ALOFT SHOULD ALSO MIX DOWN TO THE SURFACE FOR
A TIME THIS AFTERNOON...WITH WESTERLY WINDS OF 15 TO 20 MPH
EXPECTED.
EXPECT THAT GRASSLANDS IN THE SOUTHWEST ARE CURING QUICKLY.
THE LATEST ASSESSMENT FROM LAND MANAGERS INDICATED THAT SLOPE AND
BOWMAN COUNTIES WOULD LIKELY BE THE FIRST TO REACH CRITICAL FUEL
MOISTURE LEVELS AT SOME POINT. WEATHER CONDITIONS EXPECTED TODAY
WOULD WARRANT A RED FLAG MENTION FOR WILLISTON TO HETTINGER AND
WESTWARD...BUT UNDERSTAND THAT GRASSLANDS HAVE NOT YET REACHED
CRITICAL FUEL MOISTURE LEVELS.
COOLER CONDITIONS WITH HIGHER RELATIVE HUMIDITY VALUES ARE EXPECTED
ON SUNDAY...AFTER A COLD FRONTAL PASSAGE SATURDAY NIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...JV
LONG TERM...JJS
AVIATION...AYD
FIRE WEATHER...JV
AREA FORECAST DISCUSSION
NWS BISMARCK ND
625 AM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 616 AM CDT SAT AUG 1 2015
AREA OF CLOUDS WITH A FEW SPRINKLES IN WEAK THETA-E ADVECTION OVER
CENTRAL ND INTO THE JAMES RIVER VALLEY CONTINUE TO SLOWLY SHIFT
TO THE EAST. FOR EARLY MORNING UPDATE WILL ADJUST CLOUD COVER AND
ADD MENTION OF SPRINKLES...ENDING BY MID MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CDT SAT AUG 1 2015
A VERY WARM DAY TODAY HIGHLIGHTS THE SHORT TERM FORECAST.
NORTHWEST UPPER LEVEL JET FLOW CONTINUED OVER THE STATE...WITH
AN UPPER LEVEL LOW OVER HUDSON BAY AND A WARM WESTERN RIDGE OVER THE
WEST COAST AND ROCKIES. WARM AND DRY AIR WAS SOUTHWEST OF THE UPPER
LEVEL JET WITH COOLER AIR TO THE NORTHEAST.
EARLY THIS MORNING ISOLATED SHOWERS DEVELOPED...LIKELY ALONG A
BOUNDARY BETWEEN A SOUTHERLY LOW LEVEL JET ALONG WESTERN NEBRASKA
INTO THE WESTERN DAKOTAS. ENOUGH LIFT WAS OCCURRING IN A NORTHWEST-
TO-SOUTHEAST FASHION ACROSS CENTRAL NORTH DAKOTA. THE LATEST
ITERATION OF THE HRRR INDICATES THE AREA OF ISOLATED SHOWERS
SHIFTING EAST TO THE JAMES VALLEY BEFORE SUNRISE...THEN CONTINUING
EAST OUT OF THE JAMES VALLEY.
A COLD FRONT OVER THE CENTRAL CANADIAN PRAIRIE PROVINCES THIS
MORNING IS FORECAST TO MOVE SOUTH TODAY AND ENTER NORTHWESTERN NORTH
DAKOTA BY THIS EVENING...SWEEPING SOUTHEAST ACROSS THE STATE
TONIGHT. LOOK FOR A VERY WARM DAY TODAY AHEAD OF THE FRONT. WESTERLY
MIXING WINDS ALOFT SHOULD INCREASE WITH THE APPROACH OF THE FRONT
DUE TO THE INCREASING PRESSURE GRADIENT. FORECAST SOUNDINGS INDICATE
AN ADIABATIC LINK FROM THE SURFACE UP TO AROUND H700 THIS AFTERNOON.
WENT ABOVE GUIDANCE FOR MAX TEMPS AND RAISED WINDS A BIT AS WELL
FROM GUIDANCE. LOOKING AT HIGHS TODAY IN THE LOW TO MID 90S OVER
MOST OF WESTERN AND CENTRAL NORTH DAKOTA.
TONIGHT AS THE COLD FRONT SWEEPS SOUTHEAST ACROSS THE STATE...THE
BEST UPPER LEVEL FORCING RESIDES TO OUR NORTHEAST IN THE FLOW OF THE
UPPER JET - WHICH SHOULD HAVE LIFTED NORTHEAST DURING THE DAY
ALLOWING THE VERY WARM AND DRY AIR TO ADVANCE INTO CENTRAL NORTH
DAKOTA. HAVE KEPT THE SLIGHT CHANCES OF THUNDERSTORMS ACROSS THE
TURTLE MOUNTAIN AREA. COOLER AIR MOVES INTO THE STATE TONIGHT WITH
NORTHWEST WINDS BEHIND THE COLD FRONT. KEPT LOWS TONIGHT IN THE 50S
AS THE NORTHWEST WINDS WILL KEEP THE LOWER ATMOSPHERE MIXED ENOUGH
SO THAT TEMPS DO NOT DROP INTO THE 40S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 301 AM CDT SAT AUG 1 2015
COOLER TEMPERATURES EXPECTED OVER THE AREA ON SUNDAY IN THE WAKE
OF THE COLD FRONT. OTHERWISE...DRY CONDITIONS EXPECTED WITH UPPER
RIDGE AXIS SLIDING OVER THE ROCKIES AND SURFACE HIGH SETTLING OVER
THE REGION. DRY WEATHER CONTINUES INTO MONDAY WITH RIDGE AXIS
PUSHING TOWARDS THE NORTHERN PLAINS.
ACTIVE WEATHER PATTERN EXPECTED TOWARDS MID-WEEK WITH RIDGE
BREAKING DOWN AND A VARIETY OF SHORT WAVES EJECTING OVER THE AREA
FROM A BROAD UPPER LOW OVER BRITISH COLUMBIA. UNSETTLED PATTERN
CONTINUES INTO THE END OF THE WEEK AS LOW STARTS TO MAKE ITS WAY
EASTERLY. BELOW AVERAGE TEMPERATURES EXPECTED THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 616 AM CDT SAT AUG 1 2015
VFR CONDITIONS WILL CONTINUE THROUGH THE FORECAST PERIOD. LIGHT
WINDS SHOULD BECOME SOUTHERLY OR SOUTHWESTERLY AHEAD OF A COLD FRONT
THAT IS FORECAST TO MOVE THROUGH KISN AROUND 00Z...AND THROUGH KMOT
AND KDIK AROUND 04Z SATURDAY EVENING...REACHING KJMS AROUND 09Z.
SOUTHWEST WINDS COULD BE GUSTY AT TIMES AT KISN AND KDIK THIS
AFTERNOON BETWEEN 17Z AND 00Z.
&&
.FIRE WEATHER...
ISSUED AT 301 AM CDT SAT AUG 1 2015
AN ADIABATIC LAPSE RATE UP TO H700 THIS AFTERNOON WILL ALLOW
MIXING WINDS ALOFT TO LINK WITH THE SURFACE. EXPECTING 15 TO 20
MPH WINDS FOR A TIME THIS AFTERNOON IN THE WEST AS TEMPERATURES
REACH INTO THE 90S. DEWPOINTS IN THE 40S OVER SOUTHWESTERN NORTH
DAKOTA THIS MORNING ARE EXPECTED TO DROP INTO THE 30S THIS
AFTERNOON AS THE LOWER ATMOSPHERE MIXES WITH MID LEVELS.
TEMPERATURES IN THE MID 90S WITH DEWPOINTS IN THE 30S SHOULD
RESULT IN MINIMUM RELATIVE HUMIDITY VALUES IN THE 10 TO 15 PERCENT
RANGE OVER MUCH OF WESTERN NORTH DAKOTA...MAINLY ALONG AND WEST OF
A LINE FROM WILLISTON TO WATFORD CITY TO DICKINSON AND HETTINGER.
IN ADDITION...WINDS ALOFT SHOULD ALSO MIX DOWN TO THE SURFACE FOR
A TIME THIS AFTERNOON...WITH WESTERLY WINDS OF 15 TO 20 MPH
EXPECTED.
EXPECT THAT GRASSLANDS IN THE SOUTHWEST ARE CURING QUICKLY.
THE LATEST ASSESSMENT FROM LAND MANAGERS INDICATED THAT SLOPE AND
BOWMAN COUNTIES WOULD LIKELY BE THE FIRST TO REACH CRITICAL FUEL
MOISTURE LEVELS AT SOME POINT. WEATHER CONDITIONS EXPECTED TODAY
WOULD WARRANT A RED FLAG MENTION FOR WILLISTON TO HETTINGER AND
WESTWARD...BUT UNDERSTAND THAT GRASSLANDS HAVE NOT YET REACHED
CRITICAL FUEL MOISTURE LEVELS.
COOLER CONDITIONS WITH HIGHER RELATIVE HUMIDITY VALUES ARE EXPECTED
ON SUNDAY...AFTER A COLD FRONTAL PASSAGE SATURDAY NIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JJS
SHORT TERM...JV
LONG TERM...JJS
AVIATION...JV
FIRE WEATHER...JV
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1037 AM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 1027 AM CDT SAT AUG 1 2015
INITIAL SHORTWAVE ENERGY SLIGHTLY STRONGER THAN MODEL GUIDANCE
ANTICIPATED OVERNIGHT...WITH LLJ CONTINUING TO DEVELOP SCATTERED
STORMS ALONG AN ELEVATED BOUNDARY OVER SOUTH CENTRAL SD AND INTO
NEBRASKA. SHORT TERM GUIDANCE CONTINUES TO INDICATE THAT AS THE
LEAD WAVE MOVES SOUTHEAST...THE LLJ WILL GRADUALLY BACK WESTWARD
BY EARLY AFTERNOON AND SHOULD TAPER OFF THIS CONVECTION. 12Z
NAM/GFS PERFORMING VERY POORLY WITH THIS CONVECTION.
SECONDARY SHORTWAVE NOW ENTERING WESTERN ND ARRIVING SLIGHTLY
SLOWER THAN ANTICIPATED...BUT ALREADY DEVELOPING A SFC LOW WEST
OF BISMARCK. A SFC WARM FRONT STRETCHES SOUTHEAST OF THIS
LOW...OVER NORTHEASTER SD AND INTO SW MN.
BIGGEST QUESTIONS FOR THE AFTERNOON HINGE ON THIS LINGERING CLOUD
COVER...AND GRADUAL MIXDOWN OF SLIGHTLY DRIER AIR ALOFT. NAM
AGAIN VERY UNRELIABLE WITH BOUNDARY LAYER MOISTURE AT 12Z...BUT
FEEL HRRR...EXP-HRRR AND RAP FAR TOO AGGRESSIVE WITH THE MIXDOWN.
NEVERTHELESS...FOCUS FOR CONVECTION MAY SHIFT SLIGHTLY THIS
AFTERNOON...ALONG ADVANCING WARM FRONT OVER MN AND NE SD...AND
ALONG DIFFERENTIAL HEATING AXIS ACROSS OUR SWRN COUNTIES. THE
TIMING OF THIS SECONDARY WAVE IS ALSO NOT AS FAVORABLE.
FOR NOW...HAVE ADJUSTED POPS SLIGHTLY...AND LOWERED TEMPERATURES A
HAIR IN THE FAR SOUTH AND SOUTHWEST. THERE STILL APPEARS TO BE
POTENTIAL FOR A FEW CLUSTERS OF STRONG STORMS LATER TODAY...BUT
AGAIN MESOSCALE DETAILS STILL NOT RESOLVED MAY DRIVE THIS
OPPORTUNITY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CDT SAT AUG 1 2015
A SHORT WAVE PRESENTLY LOCATED OVER EASTERN MONTANA EARLY THIS
MORNING WILL CONTINUE TO SLIDE SOUTHWARD TODAY ON A NORTHWESTERLY
UPPER LEVEL FLOW...AND WILL PLAY A PART IN OUR WEATHER FOR LATER
THIS AFTERNOON. CURRENT RADAR SHOWING A LINE OF SHOWERS AND
THUNDERSTORMS DEVELOPING THROUGH SOUTH CENTRAL SD INTO NORTH CENTRAL
NE ALONG AN INSTABILITY AXIS AS MIDLEVEL THETA E ADVECTION SPREADS
INTO THAT AREA OUT AHEAD OF THE AFOREMENTIONED WAVE. MAY SEE THESE
STORMS CONTINUE OVER THAT AREA THROUGH THE MID MORNING BEFORE THE
LOW LEVEL JET WEAKENS. AFTER THAT WILL MOST LIKELY SEE CONVECTIVE
ACTIVITY WANE INTO THE AFTERNOON AS A CAP STRENGTHENS ACROSS THE
AREA. BY AFTERNOON THE SHORTWAVE BEGINS TO EXERT INFLUENCE ON THE
REGION WITH COOLING TEMPERATURES ALOFT WEAKENING THE CAP. STILL
SEEING SOME MODEL DIFFERENCES WITH REGARD TO LOWER LEVEL MOISTURE
AND RESULTANT DIFFERENCES IN THE AMOUNT OF INSTABILITY DURING THE
AFTERNOON...THOUGH EITHER WAY THERE SHOULD BE SUFFICIENT CAPE AS
TEMPERATURES WARM INTO THE UPPER 80S TO LOWER 90S TO SUPPORT
VIGOROUS UPDRAFTS IN STORMS WHICH ARE EXPECTED TO DEVELOP BY LATE
AFTERNOON THROUGH THE LOWER MISSOURI RIVER VALLEY. THIS CONVECTIVE
ACTIVITY WILL THEN BECOME MORE FOCUSED IN NORTHWESTERN IOWA AND
PORTIONS OF SOUTHWESTERN MINNESOTA BY LATE AFTERNOON AND EVENING AS
A LOW LEVEL JET STRENGTHENS OVER THAT AREA. EFFECTIVE SHEAR VALUES
LOOK TO BE RUNNING IN EXCESS OF 40 KTS...SO SEVERE STORMS WILL BE A
POSSIBILITY WITH LARGE HAIL AND DAMAGING WINDS. THINKING THAT CANNOT
COMPLETELY RULE OUT AN ISOLATED TORNADO WITH INITIAL CONVECTIVE
DEVELOPMENT THROUGH THE LOWER MISSOURI RIVER VALLEY...WITH LOW LCL
HEIGHTS AND FAIRLY STRONG 0 TO 1 KM SHEAR.
WILL SEE ANY STORMS EVOLVE EASTWARD THROUGH THE EVENING AND EARLY
NIGHT TIME HOURS AS THE SHORTWAVE SLIDES INTO CENTRAL AND EASTERN
IOWA BY EARLY SUNDAY MORNING. SOUTHWESTERLY WINDS WILL NOT BE QUITE
AS LIGHT TONIGHT...AND IT WILL BE A MILD NIGHT WITH LOWS GENERALLY
MID TO UPPER 60S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 340 AM CDT SAT AUG 1 2015
ON SUNDAY...THE COOL FRONT WILL MOVE ACROSS THE AREA...EXITING
NORTHWEST IOWA BY EARLY AFTERNOON. THIS WILL SHIFT WINDS TO THE
NORTHWEST AT 10 TO 20 MPH WITH GUSTS UP TO 30 MPH IN SW MN DURING
THE AFTERNOON. THIS WILL RESULT IN A WELL MIXED ATMOSPHERE.
DESPITE SOMEWHAT COOLER AIR ADVECTING IN AT LOW LEVEL...
TEMPERATURES ARE EXPECTED TO STILL WARM INTO THE MID 80S TO LOWER
90S DUE TO MIXING. THIS WILL ALSO MIX DOWN DRIER AIR WITH
AFTERNOON DEW POINTS IN THE LOWER 50S OVER MUCH OF SE SOUTH DAKOTA
AND SW MN DURING THE AFTERNOON. A LITTLE MORE MOISTURE CAN BE
EXPECTED IN NW IOWA. WINDS ARE EXPECTED TO DROP OFF QUICKLY ON
SUNDAY EVENING AND WITH FAIRLY DRY AIR IN PLACE MOST PLACES NORTH
OF I90 WILL SEE LOWS IN THE UPPER 50S WITH LOWER 60S SOUTH OF I90.
MODEL DIFFERENCES INCREASE ON MONDAY. THE NAM SHOWS A WEAK UPPER
LEVEL WAVE MOVING IN THE NORTHWEST FLOW. AS THIS WAVE MOVES INTO
THE SD...THE 850 MB BOUNDARY IS DRAWN NORTHWARD INTO FAR SOUTHERN
SOUTH DAKOTA AND NORTHERN IOWA. THE GFS AND 00Z ECMWF DO NOT
REALLY SHOW THIS WAVE AND INSTEAD HAVE A WEAK WAVE MOVE EAST OUT
OF COLORADO INTO THE HIGH PLAINS. AS A RESULT THE 850 MB BOUNDARY
REMAINS BETWEEN I80 AND HWY 20. HAVE GENERALLY SIDED WITH THIS
SOLUTION. AS A RESULT ON MONDAY...WHILE SKIES WILL BECOME PARTLY
CLOUDY NEAR THE MISSOURI RIVER AND INTO NW IA...IT WILL AGAIN BE
MOSTLY SUNNY ALONG AND NORTH OF I90. THERE WILL AGAIN BE DEEP
NORTHERLY FLOW IN THIS AREA AND THIS WILL RESULT IN A WELL MIXED
ATMOSPHERE. AFTERNOON DEW POINTS WILL FALL INTO THE LOWER 50S WITH
TEMPERATURES WARMING INTO THE LOW TO MID 80S. FARTHER SOUTH...WITH
A FEW MORE CLOUDS AND LESS MIXING...DEW POINTS WILL REMAIN IN THE
LOWER 60S WITH HIGHS GENERALLY IN THE MID 80S.
WITH SOME CONVERGENCE IN THE VICINITY OF THE BOUNDARY IN NRN
NEBRASKA AND LI/S AROUND -2...COULD SEE A FEW SHOWERS OR
THUNDERSTORMS DEVELOP NEAR THE MISSOURI RIVER LATE MONDAY MORNING
INTO MONDAY AFTERNOON. THE BEST CHANCE FOR PRECIPITATION WILL BE
MONDAY EVENING AS THE UPPER WAVE APPROACHES THE AREA. WHILE IT
APPEARS THE BEST CHANCE FOR PRECIPITATION WILL BE SOUTH OF HIGHWAY
20...GIVEN UNCERTAINTY IN THE LOCATION OF THE 850 MB FRONT...HAVE
SLIGHT CHANCE POPS AS FAR NORTH AS I90 ON MONDAY EVENING WITH 30
TO 40 PERCENT POPS AROUND SIOUX CITY AND STORM LAKE. WITH THE
BETTER CONVERGENCE SHIFTING TO THE SOUTH THROUGH THE NIGHT...THE
PRECIPITATION CHANCE SHOULD DECREASE AFTER MIDNIGHT.
FOR THE EXTENDED...TUESDAY THROUGH FRIDAY...THERE ARE NOT MAJOR
DIFFERENCES BETWEEN MODEL SOLUTIONS. THE GFS...ECMWF...GEFS AND
CANADIAN ALL SHOW AN UPPER LOW NEAR HUDSON BAY AND A RIDGE OVER THE
WESTERN US. THIS RIDGE GRADUALLY MOVES EAST THROUGH THE WEEK
ALTHOUGH A WEAK WAVE MOVING OVER THE RIDGE MID TO LATE WEEK WILL
PREVENT ANY WARMING ACROSS THE AREA. AND IT IS THIS WAVE THAT WILL
DEFINE ANY PRECIPITATION CHANCES. TUESDAY LOOKS PRIMARILY DRY
EXCEPT FOR THE POSSIBILITY OF THUNDERSTORMS IN THE MISSOURI
VALLEY IN THE LATE AFTERNOON AND EVENING WHERE THERE IS MORE
INSTABILITY. WITH LITTLE IF ANY RAINFALL...HIGHS WILL GENERALLY BE
IN THE LOWER 80S. WEDNESDAY WILL MOST LIKELY BE DRY AS WELL
ALTHOUGH THE FASTER ECMWF DOES BRING THE WAVE EAST BY LATE
WEDNESDAY AFTERNOON. FOR THIS REASON HAVE A SLIGHT CHANCE OF
THUNDERSTORMS ON WEDNESDAY. ALL MODELS BRING THIS WAVE THROUGH
LATER WEDNESDAY NIGHT AND THURSDAY WHEN THE BEST CHANCE FOR
THUNDERSTORMS EXIST. THUNDERSTORMS CHANCES DECREASE THURSDAY NIGHT
AND FRIDAY. WITH MORE CLOUDS AND THE CHANCE OF RAIN...HIGHS
WEDNESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 70S TO
LOWER 80S. LOWS WILL BE FROM THE UPPER 50S TO LOWER 60S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 617 AM CDT SAT AUG 1 2015
AREAS OF IFR FOG THROUGH THE LOWER MISSOURI RIVER VALLEY WILL
DISSIPATE AFTER 13Z. OTHERWISE...VFR CONDITIONS INTO THE AFTERNOON
WHEN SCATTERED THUNDERSTORMS WILL DEVELOP THROUGH THE LOWER JAMES
RIVER VALLEY/MISSOURI RIVER VALLEY. THESE THUNDERSTORMS WILL THEN
PUSH TO THE EAST THROUGH NORTHWESTERN IOWA DURING THE EVENING. THE
GREATER CHANCES OF STORMS WILL BE SOUTH OF INTERSTATE 90...AND
MENTIONED IN THE KFSD AN KSUX TAFS.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...DUX
SHORT TERM...JM
LONG TERM...SCHUMACHER
AVIATION...JM
AREA FORECAST DISCUSSION
NWS PUEBLO CO
241 PM MDT SAT AUG 1 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 238 PM MDT SAT AUG 1 2015
...TYPICAL AUGUST WEATHER CONTINUES ON SUNDAY...
FAIRLY TYPICAL SUMMER PATTERN REMAINS IN PLACE OVER SE CO. WITH
MONSOONAL PLUME CIRCULATING CLOCKWISE AROUND THE UPPER HIGH CENTERED
OVER NM...BEST T-STORM COVERAGE CONTINUES TO BE OVER WRN AND SRN
PORTIONS OF THE CWA. NEWLY OPERATIONAL RADAR IN THE SAN JUANS SHOWS
WIDESPREAD CONVECTION OVER THE SW MTS...JUSTIFYING LIKELY POPS FOR
THE BALANCE OF THE AFTERNOON AND INTO EARLY EVE. MORE QUESTIONABLE
WHETHER STORMS WILL SURVIVE MOVING ONTO THE SERN PLAINS E OF I-
25...BUT ISOLD POPS LOOK APPROPRIATE THERE. TEMPS CONTINUE TO BE
IN THE LOWER 90S FOR THE PLAINS...70S FOR THE HIGH VALLEY AREAS.
EXPECT MOST OF THE T-STORM ACTIVITY TO WANE AFTER SUNSET...HOWEVER
LATEST HRRR AND OTHER GUIDANCE SUGGESTS CONTINUED ISOLD ACTIVITY
OVER THE SW MTS AND SURROUNDING AREAS...SO WILL MAINTAIN AT LEAST
LOW POPS THROUGH THE NIGHT FOR THIS AREA. SOME MODEL SOUNDINGS STILL
SUPPORT LOW CLOUDS OR POSSIBLY EVEN SOME FOG FOR THE SAN LUIS VALLEY
IF SUFFICIENT PRECIP CAN FALL THIS AFTERNOON OR EVE.
TOMORROW...MORE OF THE SAME...BUT A WEAK SHORTWAVE PASSING THROUGH
NW FLOW ON THE E SIDE OF THE UPPER RIDGE COULD SPARK A FEW MORE
STORMS THAN WE ARE CURRENTLY SEEING...ESPECIALLY OVER THE SERN
MTS. SFC WINDS SHIFT TO A STRONGER UPSLOPE COMPONENT SUN
AFTERNOON... WHICH WILL KEEP THE BEST FORCING FOR STORMS ANCHORED
ALONG THE MTS AND ADJACENT LOWLANDS ALONG THE I-25 CORRIDOR.
TEMPS AGAIN SHOULD BE IN THE LOWER TO MID 90S OVER THE PLAINS. ROSE
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 238 PM MDT SAT AUG 1 2015
SUN NIGHT AN UPR TROF IS FORECAST TO EXTEND FROM THE GREAT BASIN
REGION AND ACRS CO. BOTH THE NAM AND GFS SHOW A SHORTWAVE TROF
MOVING INTO THE SERN CORNER OF CO OVERNIGHT AND INTO MON
MORNING...BUT THEY DISAGREE ON ITS IMPACT. BOT MODELS SHOW PCPN
CONTINUING THRU THE NIGHT OVR THE CONTDVD WITH THE POTENTIAL FOR
SOME ISOLD PCPN OVR THE ERN MTNS. FOR FAR ERN PORTIONS OF THE
FORECAST AREA...THE NAM HAS MAINLY SOME ISOLD PCPN OVR THE SERN
CORNER THRU THE NIGHT AND MON MORNING...BUT THE GFS HAS MORE
WIDESPREAD CHANCES OVR THE SERN PLAINS. SINCE THERE IS A DISTURBANCE
IN THE AREA...WL KEEP SOME ISOLD POPS ACRS THE SERN PLAINS THRU THE
NIGHT. THRU THE DAY MON...THAT UPR TROF CONTINUES WORKING ITS WAY
NORTHEASTWARD INTO ID...WY AND NERN CO. THE GFS AND NAM HAVE SCT
PCPN OVR THE HYR TRRN ON MON...WHILE THE NAM IS MAINLY DRY OVR THE
SERN PLAINS IN THE AFTERNOON AND EVENING...BUT THE GFS HINTS AT
ISOLD TO SCT PCPN. MON NIGHT THE NAM SHOWS PCPN ACRS THE FORECAST
AREA ENDING BY LATE EVENING...BUT THE GFS CONTINUES PCPN OVR THE FAR
ERN BORDER AREA INTO THE LATE NIGHT HOURS.
TUE AN UPR RIDGE BUILDS OVR THE AREA AND REMAINS IN PLACE ON
WED...WHICH WL KEEP THE MONSOON MSTR TO THE SOUTH OF THE FORECAST
AREA. SO...DRIER CONDITIONS CAN BE EXPECTED ALTHOUGH THERE MAY STILL
BE ENOUGH MSTR OVR THE AREA FOR A FEW AFTERNOON AND EVENING MTN AREA
SHOWERS/TSTMS. ON THU A DISTURBANCE IS FORECAST TO MOVE ACRS
WY...THEN PUSHING A FRONT THRU ERN CO. THE ECMWF DEVELOPS AND MCS
OVR ERN FOR THU NIGHT...WHILE THE GFS DOES NOT AND LEAVES THE AREA
RATHER DRY. FOR NOW WL GO WITH THE DRY SOLUTION AND SEE HOW THE
SITUATION DEVELOPS.
FRI THE UPR RIDGE WL BE CENTERED TO THE SOUTH OF CO. THE ECMWF
SHOWS THE POTENTIAL FOR A LITTLE MORE MSTR TO WORK ITS WAY BACK
TOWARD CO...BUT THE GFS IS STILL FAIRLY DRY THROUGH SAT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 238 PM MDT SAT AUG 1 2015
MAIN AVN CONCERN CONTINUES TO BE TS POTENTIAL AT THE TAF SITES...AT
LEAST THROUGH ABOUT 02-03Z THIS EVE AT KCOS AND KPUB. COULD SEE A
FEW MORE STORMS OVER PORTIONS OF THE SAN LUIS VALLEY THROUGH TONIGHT
AS THE MONSOON REMAINS ACTIVE OVER NERN AZ AND NW NM. DEPENDING ON
EXTENT OF PRECIP...SOME LOW CIGS WILL BE POSSIBLE FOR KALS OR VC
EARLY SUN MORNING. OTHERWISE...VFR AND LIGHT WINDS WILL CONTINUE
FOR MOST OF SE CO. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ROSE
LONG TERM...28
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS TOPEKA KS
326 PM CDT SAT AUG 1 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 326 PM CDT SAT AUG 1 2015
19Z WATER VAPOR IMAGERY SHOWS NORTHWEST FLOW ACROSS THE NORTHERN AND
CENTRAL PLAINS WHILE THE CENTER OF A MID LEVEL RIDGE SITS OVER WEST
TX. THE RIDGE AXIS EXTENDED NORTHWEST INTO OR. THE RAP ANALYSIS
SUGGESTS THERE ARE ONLY A COUPLE WEAK VORT MAXIMUM UPSTREAM. ONE
OVER EASTERN NEB AND ANOTHER MOVING INTO SD. AT THE SURFACE, A MESO
HIGH REMAIN OVER CENTRAL NEB WHILE OUTFLOW BOUNDARIES FROM MORNING
CONVECTION HAVE BECOME MORE DIFFUSE ACROSS CENTRAL AND EASTERN KS.
FOR THIS AFTERNOON AND THIS EVENING, THERE REMAINS AN OUTSIDE CHANCE
FOR A STORM TO DEVELOP AS OBJECTIVE ANALYSIS SHOWS MORE THAN ENOUGH
INSTABILITY. HOWEVER SURFACE FLOW HAS BEEN RATHER WEAK SO
CONVERGENCE AND LIFT ALONG ANY OF THE BOUNDARIES HAS ALSO BEEN
RATHER WEAK. SATELLITE SHOWS LITTLE DEVELOPMENT TO THE CU FIELD
ACROSS THE AREA INDICATING THERE HASN`T BEEN MUCH FORCING AS WELL.
AND ANY WEAK VORTICITY ADVECTION FROM THE LEFT OVER CONVECTION IN
EASTERN NEB IS LIKELY PROPAGATING INTO MO. BECAUSE OF THIS THINK THE
CHANCES FOR ANY SPOT TO RECEIVE RAIN IS ONLY ABOUT 10 PERCENT AND
NOT HIGH ENOUGH TO MENTION IN THE FORECAST. ONCE THE BOUNDARY LAYER
STARTS TO COOL, THE THREAT FOR THUNDERSTORMS SHOULD DIMINISH.
OVERNIGHT, MODELS SHOW THE LOW LEVEL JET SETTING UP ACROSS NEB AND
IA WITH NO REAL ORGANIZED ISENTROPIC LIFT ACROSS THE FORECAST AREA.
BECAUSE OF THIS HAVE A DRY FORECAST GOING THROUGH THE NIGHT. THERE
SHOULD BE MOSTLY CLEAR SKIES, SO THINK WITH SOME RADIATIONAL COOLING
LOWS WILL FALL INTO THE UPPER 60S TO AROUND 70.
FOR SUNDAY, THE SETUP LOOKS VERY SIMILAR TO TODAY WITH DECENT
SURFACE BASED INSTABILITY DEVELOPING AND NOT MUCH INHIBITION TO
CONVECTION. WITH A LACK OF LARGE SCALE FORCING, PRECIP CHANCES LOOK
UNLIKELY UNTIL A TROUGH AXIS APPROACHES NORTH CENTRAL KS LATE IN THE
DAY. MOST MODEL SOLUTIONS SHOW THIS BOUNDARY MOVING INTO THE
FORECAST AREA LATE IN THE AFTERNOON BUT THE GFS IS REALLY THE ONLY
ONE THAT DEVELOPS CONVECTION. THE GFS ALSO IS THE WARMEST SOLUTION
AND MAY BE A LITTLE EAGER TO BREAK WHAT CAP THERE IS. WHILE PRECIP
CHANCES DON`T LOOK GREAT, IT`S DIFFICULT TO RULE OUT A CHANCE SO
HAVE SLIGHT CHANCE POPS IN THE FORECAST FOR THE LATE AFTERNOON. WITH
850 TEMPS SLIGHTLY WARMER THAN TODAY, HAVE HIGHS A DEGREE OR SO
WARMER WITH GENERALLY MID 90S EXPECTED.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 326 PM CDT SAT AUG 1 2015
SUNDAY EVENING WILL CONTINUE TO KEEP LOW PRECIPITATION CHANCES ALONG
THE WEAK FRONTAL BOUNDARY AS WELL AS THE INSTABILITY AXIS ACROSS THE
NORTHERN CWA. WILL LITTLE TO NO UPPER SUPPORT AND WEAK SURFACE
CONVERGENCE EXPECT ANY CONVECTION TO BE ON THE WANE AFTER SUNSET.
LOWS SUNDAY NIGHT WILL COOL INTO THE UPPER 60S TO LOWER 70S.
MONDAY FOR MUCH OF THE DAY LOOKS DRY WITH INCREASING CHANCES FROM
LATE AFTERNOON THROUGH EARLY MORNING HOURS ON TUESDAY ESPECIALLY
NEAR THE NEBRASKA BORDER NEAR THE VICINITY OF THE SURFACE FRONTAL
BOUNDARY IN SOUTHERN NEBRASKA. LOW LEVEL JET WILL INCREASE FROM THE
SOUTH AND SOUTHWEST MONDAY NIGHT BEFORE WEAKENING TUESDAY MORNING.
MODELS CONTINUE TO SHOW MID LEVEL SHORTWAVE MOVING THROUGH THE
PLAINS TUESDAY AND TUESDAY NIGHT.
WEDNESDAY THROUGH SATURDAY WILL BE MARKED BY COOLER TEMPERATURES
WITH PRECIPITATION CHANCES OFF AND ON AS WAVES MOVE THROUGH THE
NEARLY ZONAL FLOW ACROSS THE CENTRAL PLAINS. HIGH PRESSURE NOSES
INTO EASTERN KANSAS ON THURSDAY WITH A FRONTAL BOUNDARY SOUTH OF THE
FORECAST AREA. APPROACHING SHORTWAVE TROUGH AND INCREASING
ISENTROPIC LIFT OVER THE FRONT WILL KEEP A CHANCE FOR ELEVATED
THUNDERSTORMS THURSDAY NIGHT THEN CONTINUE ON FRIDAY WITH PASSAGE OF
THE UPPER TROUGH. COOLER HIGH PRESSURE BUILDS IN SATURDAY. COOLER
HIGH TEMPERATURES ARE EXPECTED FROM WEDNESDAY THROUGH SATURDAY IN
THE 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1210 PM CDT SAT AUG 1 2015
MODELS SHOW A CONDITIONALLY UNSTABLE ATMOSPHERE. THERE ARE A
COUPLE WEAK OUTFLOW BOUNDARIES WITH LITTLE IF ANY CONVERGENCE
ALONG THEM. FORCING IS ALSO WEAK...LIKELY COMING FROM REMNANT
CONVECTION OVER EASTERN NEB. SO THERE COULD BE ISOLATED STORMS
THROUGH THE AFTERNOON BUT TS PREDICTABILITY IS TO LOW TO INCLUDE
IN THE FORECAST WITH ANY CONFIDENCE. THEREFORE A VFR CONDITIONS
ARE FORECAST TO PERSIST. TS CHANCES SHOULD LESSEN BY THE EARLY
EVENING WITH THE LOSS OF DAYTIME HEATING AND SURFACE INSTABILITY.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...WOLTERS
LONG TERM...53
AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
533 PM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 531 PM CDT SAT AUG 1 2015
UPDATED AVIATION SECTION FOR 00Z TAF ISSUANCE.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 223 PM CDT SAT AUG 1 2015
A BAND OF ENHANCED CU EXTENDING FROM CENTRAL MISSOURI INTO OUR
SOUTHEAST MISSOURI COUNTIES IS ASSOCIATED WITH AN AREA OF HIGHER
THETA-E AIR AT THE SURFACE...AND MAY PROVIDE A FOCUS FOR
CONVECTIVE DEVELOPMENT THIS AFTERNOON AND EVENING. HAVE ALREADY
SEEN A 30KT PEAK WIND AT KSZL AS THUNDERSTORMS PASSED THROUGH THAT
AREA...AND THAT POTENTIAL SHOULD CONTINUE SOUTHEASTWARD
INTO/THROUGH SOUTHEAST MISSOURI LATE THIS AFTERNOON AND THIS
EVENING.
FOR NOW JUST HAVE A 20 PERCENT POP FOR MOST OF SOUTHEAST MISSOURI
THROUGH THE EVENING...AS THE HRRR AND ARW/NMM WRF RUNS HAVE ONLY
VERY ISOLATED CONVECTION IN OUR AREA. WILL MONITOR RADAR TRENDS
AND RAMP UP POPS AS NECESSARY. LOW-LEVEL MOISTURE SEEMS TO BE THE
LIMITING FACTOR TODAY...SO IT MAY BE DIFFICULT TO SUSTAIN AN
UPDRAFT. THERE IS A LOT OF DRY AIR THROUGHOUT THE COLUMN...SO IT
WILL NOT BE SURPRISING TO SEE A FEW HEALTHY WIND GUSTS IF A STORM
SURVIVES INTO OUR AREA.
ELSEWHERE ACROSS THE AREA...DEWPOINTS ARE MIXING OUT PRETTY
WELL...WITH SEVERAL SITES IN THE 50S ACROSS THE EVANSVILLE TRI
STATE. WITH A SIGNIFICANT DEWPOINT GRADIENT AND DECENT RADIATIONAL
COOLING EXPECTED TONIGHT...WE COULD SEE A FAIRLY LARGE RANGE OF
LOWS TONIGHT. TRIED TO INCREASE THE GRADIENT A BIT BY LOWERING LOWS
IN THE NORTHEAST AND INCREASING THEM SLIGHTLY IN THE SOUTHWEST.
SURFACE HIGH PRESSURE WILL PUSH OUT OF THE AREA FOR SUNDAY...AS
OUR NEXT COLD FRONT DESCENDS THROUGH THE GREAT LAKES AND THE UPPER
MIDWEST. THIS WILL ALLOW DEWPOINTS TO RECOVER A BIT FROM TODAYS
HEALTHY MIXING. TEMPERATURES WILL ALSO INCREASE A BIT IN THE
NORTHEAST WITH THE ENTIRE AREA EXPECTED TO REACH THE LOWER 90S.
THERE IS SOME POTENTIAL FOR CONVECTION TO MOVE OFF OF THE
APPROACHING FRONT AND NEAR OUR SOUTHWEST INDIANA COUNTIES LATE
SUNDAY NIGHT AND EARLY MONDAY MORNING. COULD HAVE INSERTED A
SLIGHT CHANCE UP THERE JUST TO BE SAFE...BUT THE CONSENSUS OF
NEIGHBORING FORECAST OFFICES WAS TO KEEP IT DRY.
THE CONSENSUS OF 12Z MODEL DATA IS TO DRAG THE COLD FRONT SLOWLY
SOUTHWARD THROUGH THE REGION MONDAY AFTERNOON AND EVENING. THERE
IS LITTLE CONVERGENCE ABOUT IT UNTIL THE EVENING OVER THE SOUTHERN
THIRD OF THE AREA. TOYED WITH INSERTING A LOW CHANCE POP...BUT
ENDED UP LEAVING IT DRY DUE TO THE LACK OF DEVELOPMENT IN THE
MODELS AND ASSOCIATED LOW MOS POPS.
WITH DEWPOINTS JUMPING BACK INTO THE LOWER 70S AND TEMPERATURES
IN THE LOW TO MID 90S MONDAY...HEAT INDICES OVER MUCH OF THE
SOUTHERN HALF OF THE REGION WILL TOP OUT AROUND 100 FOR A FEW
HOURS.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 223 PM CDT SAT AUG 1 2015
EXTENDED FORECAST REMAINS PRETTY MURKY. MODELS CONTINUE TO BRING AN
UPPER LEVEL TROF ACROSS THE REGION TUESDAY NIGHT INTO WEDNESDAY
NIGHT AS A SURFACE FRONT SAGS SOUTH INTO THE AREA. MODELS ARE IN
AGREEMENT THAT THE FRONTAL BOUNDARY WILL LINGER IN THE MIDDLE
MISSISSIPPI/LOWER OHIO VALLEY THROUGH THE WEEK, BUT DIFFER IN TIMING
IN UPPER LEVEL WAVES, THUS MAKING TIMING OF BEST CHANCES OF
CONVECTION CHALLENGING. GFS AND CANADIAN ARE IN GOOD AGREEMENT ON
THE TUESDAY NIGHT INTO WEDNESDAY NIGHT UPPER WAVE. AFTER SOME
SLIGHT TO LOW CHANCE POPS FOR SHOWERS AND THUNDERSTORMS CREEP INTO
NORTHERN AND WESTERN PORTIONS OF THE PAH ON TUESDAY, BETTER CHANCES
WILL SPREAD ACROSS THE REGION TUESDAY NIGHT WITH THE APPROACH OF THE
UPPER WAVE. WENT WITH GOOD CHANCE POPS ACROSS ALL OF OUR COUNTIES
WEDNESDAY AND WEDNESDAY NIGHT. BEYOND WEDNESDAY NIGHT, KEPT POPS IN
THE SLIGHT TO LOW CHANCE CATEGORY THROUGH FRIDAY NIGHT DUE TO TIMING
UNCERTAINTIES. ON SATURDAY, AN UPPER LEVEL HIGH BUILDING OVER TEXAS
WILL KEEP OUR AREA IN NORTHWEST FLOW, BUT MODELS KEEP US DRY, AND
WENT WITH A DRY FORECAST.
TUESDAY INTO TUESDAY NIGHT WILL REMAIN MUGGY WITH HIGHS IN THE UPPER
80S TO LOWER 90S AND LOWS IN THE LOWER 70S. WEDNESDAY WILL BE A FEW
DEGREES COOLER MAINLY DUE TO PRECIPITATION AND CLOUD COVER.
THURSDAY INTO FRIDAY TEMPERATURES ARE A LITTLE TRICKIER DUE TO
UNCERTAINTY OF THE LOCATION OF THE FRONT. FOR NOW KEPT READINGS
NEAR TO A LITTLE BELOW NORMAL. BY SATURDAY WE SHOULD HAVE NORTH TO
NORTHWEST FLOW AT THE SURFACE, WHICH WILL DROP BACK DEW POINTS A FEW
DEGREES.
&&
.AVIATION...
ISSUED AT 531 PM CDT SAT AUG 1 2015
THETA-3 CONVERGENCE ALONG/JUST WEST OF MS RIVER IN ECNTL MO HAS
LED TO SOME BLOWOFF SCT-BKN MID CLOUD AFFECTING PRIMARILY KCGI
(BUT ALSO KPAH) EARLY THIS EVENING...AND SHOULD DISSIPATE LATER
THIS EVENING. OVERNIGHT FEW-SCT HIGH CLOUDS AND LGT WINDS MAY
ALLOW SOME PATCHY MVFR FOG...ESP AT MORE PRONE KCGI. LITTLE CHANGE
TO INHERITED SCT HIGH CLOUD TMRW WITH LIGHT SOUTHERLYS DEVELOPING.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PADUCAH KY
302 PM CDT SAT AUG 1 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 223 PM CDT SAT AUG 1 2015
A BAND OF ENHANCED CU EXTENDING FROM CENTRAL MISSOURI INTO OUR
SOUTHEAST MISSOURI COUNTIES IS ASSOCIATED WITH AN AREA OF HIGHER
THETA-E AIR AT THE SURFACE...AND MAY PROVIDE A FOCUS FOR
CONVECTIVE DEVELOPMENT THIS AFTERNOON AND EVENING. HAVE ALREADY
SEEN A 30KT PEAK WIND AT KSZL AS THUNDERSTORMS PASSED THROUGH THAT
AREA...AND THAT POTENTIAL SHOULD CONTINUE SOUTHEASTWARD
INTO/THROUGH SOUTHEAST MISSOURI LATE THIS AFTERNOON AND THIS
EVENING.
FOR NOW JUST HAVE A 20 PERCENT POP FOR MOST OF SOUTHEAST MISSOURI
THROUGH THE EVENING...AS THE HRRR AND ARW/NMM WRF RUNS HAVE ONLY
VERY ISOLATED CONVECTION IN OUR AREA. WILL MONITOR RADAR TRENDS
AND RAMP UP POPS AS NECESSARY. LOW-LEVEL MOISTURE SEEMS TO BE THE
LIMITING FACTOR TODAY...SO IT MAY BE DIFFICULT TO SUSTAIN AN
UPDRAFT. THERE IS A LOT OF DRY AIR THROUGHOUT THE COLUMN...SO IT
WILL NOT BE SURPRISING TO SEE A FEW HEALTHY WIND GUSTS IF A STORM
SURVIVES INTO OUR AREA.
ELSEWHERE ACROSS THE AREA...DEWPOINTS ARE MIXING OUT PRETTY
WELL...WITH SEVERAL SITES IN THE 50S ACROSS THE EVANSVILLE TRI
STATE. WITH A SIGNIFICANT DEWPOINT GRADIENT AND DECENT RADIATIONAL
COOLING EXPECTED TONIGHT...WE COULD SEE A FAIRLY LARGE RANGE OF
LOWS TONIGHT. TRIED TO INCREASE THE GRADIENT A BIT BY LOWERING LOWS
IN THE NORTHEAST AND INCREASING THEM SLIGHTLY IN THE SOUTHWEST.
SURFACE HIGH PRESSURE WILL PUSH OUT OF THE AREA FOR SUNDAY...AS
OUR NEXT COLD FRONT DESCENDS THROUGH THE GREAT LAKES AND THE UPPER
MIDWEST. THIS WILL ALLOW DEWPOINTS TO RECOVER A BIT FROM TODAYS
HEALTHY MIXING. TEMPERATURES WILL ALSO INCREASE A BIT IN THE
NORTHEAST WITH THE ENTIRE AREA EXPECTED TO REACH THE LOWER 90S.
THERE IS SOME POTENTIAL FOR CONVECTION TO MOVE OFF OF THE
APPROACHING FRONT AND NEAR OUR SOUTHWEST INDIANA COUNTIES LATE
SUNDAY NIGHT AND EARLY MONDAY MORNING. COULD HAVE INSERTED A
SLIGHT CHANCE UP THERE JUST TO BE SAFE...BUT THE CONSENSUS OF
NEIGHBORING FORECAST OFFICES WAS TO KEEP IT DRY.
THE CONSENSUS OF 12Z MODEL DATA IS TO DRAG THE COLD FRONT SLOWLY
SOUTHWARD THROUGH THE REGION MONDAY AFTERNOON AND EVENING. THERE
IS LITTLE CONVERGENCE ABOUT IT UNTIL THE EVENING OVER THE SOUTHERN
THIRD OF THE AREA. TOYED WITH INSERTING A LOW CHANCE POP...BUT
ENDED UP LEAVING IT DRY DUE TO THE LACK OF DEVELOPMENT IN THE
MODELS AND ASSOCIATED LOW MOS POPS.
WITH DEWPOINTS JUMPING BACK INTO THE LOWER 70S AND TEMPERATURES
IN THE LOW TO MID 90S MONDAY...HEAT INDICES OVER MUCH OF THE
SOUTHERN HALF OF THE REGION WILL TOP OUT AROUND 100 FOR A FEW
HOURS.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 223 PM CDT SAT AUG 1 2015
EXTENDED FORECAST REMAINS PRETTY MURKY. MODELS CONTINUE TO BRING AN
UPPER LEVEL TROF ACROSS THE REGION TUESDAY NIGHT INTO WEDNESDAY
NIGHT AS A SURFACE FRONT SAGS SOUTH INTO THE AREA. MODELS ARE IN
AGREEMENT THAT THE FRONTAL BOUNDARY WILL LINGER IN THE MIDDLE
MISSISSIPPI/LOWER OHIO VALLEY THROUGH THE WEEK, BUT DIFFER IN TIMING
IN UPPER LEVEL WAVES, THUS MAKING TIMING OF BEST CHANCES OF
CONVECTION CHALLENGING. GFS AND CANADIAN ARE IN GOOD AGREEMENT ON
THE TUESDAY NIGHT INTO WEDNESDAY NIGHT UPPER WAVE. AFTER SOME
SLIGHT TO LOW CHANCE POPS FOR SHOWERS AND THUNDERSTORMS CREEP INTO
NORTHERN AND WESTERN PORTIONS OF THE PAH ON TUESDAY, BETTER CHANCES
WILL SPREAD ACROSS THE REGION TUESDAY NIGHT WITH THE APPROACH OF THE
UPPER WAVE. WENT WITH GOOD CHANCE POPS ACROSS ALL OF OUR COUNTIES
WEDNESDAY AND WEDNESDAY NIGHT. BEYOND WEDNESDAY NIGHT, KEPT POPS IN
THE SLIGHT TO LOW CHANCE CATEGORY THROUGH FRIDAY NIGHT DUE TO TIMING
UNCERTAINTIES. ON SATURDAY, AN UPPER LEVEL HIGH BUILDING OVER TEXAS
WILL KEEP OUR AREA IN NORTHWEST FLOW, BUT MODELS KEEP US DRY, AND
WENT WITH A DRY FORECAST.
TUESDAY INTO TUESDAY NIGHT WILL REMAIN MUGGY WITH HIGHS IN THE UPPER
80S TO LOWER 90S AND LOWS IN THE LOWER 70S. WEDNESDAY WILL BE A FEW
DEGREES COOLER MAINLY DUE TO PRECIPITATION AND CLOUD COVER.
THURSDAY INTO FRIDAY TEMPERATURES ARE A LITTLE TRICKIER DUE TO
UNCERTAINTY OF THE LOCATION OF THE FRONT. FOR NOW KEPT READINGS
NEAR TO A LITTLE BELOW NORMAL. BY SATURDAY WE SHOULD HAVE NORTH TO
NORTHWEST FLOW AT THE SURFACE, WHICH WILL DROP BACK DEW POINTS A FEW
DEGREES.
&&
.AVIATION...
ISSUED AT 1228 PM CDT SAT AUG 1 2015
INFLUENCE OF SFC HIGH PRESSURE WILL LEAD TO MAINLY VFR CONDITIONS
THROUGHOUT TAF PERIOD. THERE COULD BE SOME MVFR/IFR FOG AT KCGI
AND KPAH EARLY TMRW MORNING. ISOLATED VCTS COULD GET CLOSE TO KCGI
LATE THIS AFTERNOON/EARLY EVENING BUT CHANCE TOO LOW TO MENTION AT
THIS TIME. WINDS WILL BE LIGHT OUT OF THE NORTH TODAY AND SWITCH
AROUND TO THE SOUTH TMRW MORNING.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DRS
LONG TERM...RST
AVIATION...SP
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
228 PM EDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 220 PM EDT SAT AUG 1 2015
HOURLY GRIDS HAVE AGAIN BEEN FRESHENED UP BASED ON RECENT OBSERVATIONS.
A FEW CU HAVE DEVELOPED AS A WEAK BOUNDARY SLIPS SOUTH. SOME
DEBRIS CLOUDS WILL CONTINUE TO PASS BY IN THE FLOW FROM CONVECTION
OVER THE MIDWEST AND PLAINS. BEHIND THE BOUNDARY...WINDS ARE
SHIFTING TO MORE OF A NORTHWESTERLY DIRECTION AND REINFORCING A
RELATIVELY DRY AIRMASS ACROSS THE AREA. THERE HAS BEEN ON CHANGES
TO THE FORECAST REASONING AND NO SIGNIFICANT CHANGES WERE NEEDED
AT THIS POINT.
UPDATE ISSUED AT 1100 AM EDT SAT AUG 1 2015
GRIDS HAVE BEEN TOUCHED UP BASED ON RECENT OBSERVATIONS AND
TRENDS. A WEAK MOISTURE STARVED COLD FRONT IS DROPPING SOUTH
ACROSS THE REGION TODAY AND HAVE LITTLE EFFECT OTHER THAN SHIFT
WINDS TO MORE OF A NORTHWEST DIRECTION BEHIND IT AS ANOTHER SFC
HIGH BUILDS IN. THIS HIGH WILL ALSO KEEP DEWPOINTS IN THE UPPER
50S TO LOWER 60S RANGE THROUGH TONIGHT.
UPDATE ISSUED AT 715 AM EDT SAT AUG 1 2015
TOUCHED UP THE GRIDS PER THE LATEST OBS AND TRENDS. THESE HAVE
BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 305 AM EDT SAT AUG 1 2015
06Z SFC ANALYSIS SHOWS THAT HIGH PRESSURE REMAINS IN CONTROL OF
EAST KENTUCKY/S WEATHER THIS EARLY MORNING. THIS HIGH HAS KEPT
CLOUD COVER TO A MINIMUM AND IS SUPPORTING A DECENT RIDGE TO
VALLEY TEMPERATURE SPLIT ON THE ORDER OF 5 TO 10 DEGREES. AT THE
SAME TIME DEWPOINTS ARE RUNNING IN THE LOWER 60S. AS TEMPERATURES
CONTINUE TO RADIATE LOWER FOR THE REST OF THE NIGHT THE DEWPOINTS
WILL ALSO CREEP DOWN...BUT IN THE DEEPER VALLEYS PROBABLY NOT FAST
ENOUGH TO PREVENT THE DEVELOPMENT OF FOG...ESPECIALLY NEAR RIVERS
AND BODIES OF WATER. WINDS WILL BE LIGHT THROUGH DAWN PERHAPS
CONTRIBUTING TO THE LOCALLY DENSE FOG IN THE MORE SHELTERED RIVER
VALLEY SPOTS.
THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE LONGWAVE PATTERN
AS THEY ALL DEPICT A SLOWLY DEEPENING...LARGE TROUGH THROUGH THE
NORTHEAST PORTION OF THE CONTINENT STRETCHING SOUTH THROUGH THE
OHIO VALLEY OVER THE WEEKEND. THE NORTHWEST FLOW ASSOCIATED WITH
THIS WILL BRING MINOR SHORTWAVES OVER KENTUCKY DURING THE PERIOD
BUT NOT MUCH IN THE WAY OF MESOSCALE AMPLIFICATION UNTIL PERHAPS
SUNDAY AFTERNOON WHEN A HEALTHIER ONE PASSES BY TO THE NORTH. THE
NAM CONTINUES TO BE ON THE STRONGER SIDE OF THE MODEL SPECTRUM
WITH THE LARGER TROUGH AND THIS WAVE LATE IN THE PERIOD.
ACCORDINGLY...HAVE GONE WITH MORE OF A MODEL BLEND FAVORING A MIX
OF THE ECMWF AND GFS OUTSIDE OF THE NEAR TERM WHERE THE HRRR AND
NAM12 ARE REASONABLE.
SENSIBLE WEATHER WILL FEATURE A VERY PLEASANT MID SUMMER WEEKEND
AS THE AFTERNOON WARMTH IS KEPT COMFORTABLE BY RELATIVELY LOW
HUMIDITIES WROUGHT BY A MIDDAY AND AFTERNOON MIX DOWN OF DRIER
AIR FROM THE MID LEVELS. THIS WILL KEEP CLOUD COVER TO A MINIMUM
THROUGH THE PERIOD AND ALSO LEAD TO ANOTHER NIGHT OF GOOD
RADIATIONAL COOLING FOR SUNDAY MORNING. SIMILARLY...PATCHY FOG
WILL LIKELY BE LIMITED TO THE DEEPER RIVER VALLEY LOCATIONS BOTH
THIS MORNING AND SUNDAY MORNING...THOUGH LOCALLY DENSE POCKETS
WILL BE POSSIBLE AS WELL.
AGAIN USED THE SHORTBLEND MODEL AS A STARTING POINT FOR THE
T/TD/WIND GRIDS THROUGH THE DAY FOLLOWED BY THE SUPERBLEND INTO
SUNDAY. DID MAKE SOME SIGNIFICANT ADJUSTMENTS TO TEMPERATURES
THIS MORNING AND TONIGHT WITH RESPECT TO RIDGE AND VALLEY
DIFFERENCES ONCE...AND AS...THE INVERSION IS IN PLACE. AS FOR
POPS...KEPT THEM LOW AND IN LINE WITH THE DRIER MET GUIDANCE.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 358 AM EDT SAT AUG 1 2015
THE EXTENDED PERIOD BEGINS WITH THE UPPER LEVEL PATTERN FEATURING A
RIDGE OVER THE WESTERN CONUS AND A TROUGH OVER THE EAST AND A
CLOSED LOW CENTERED JUST SOUTH OF THE HUDSON BAY AREA. THIS
PATTERN...THOUGH WITH SOME SHIFTING OF FEATURES EACH
DAY...REMAINS IN PLACE FOR JUST ABOUT THE ENTIRE EXTENDED. TO
START THE EXTENDED...A WEAK SHORTWAVE WILL PASS THROUGH THE LOWER
GREAT LAKES REGION BRINGING A SURFACE COLD FRONT ACROSS NORTHERN
KENTUCKY AND THE CHANCE FOR SOME AFTERNOON SHOWERS AND
THUNDERSTORMS. BY TUESDAY...A SURFACE STATIONARY BOUNDARY SETS UP
ACROSS SOUTHERN OH...IN...AND IL ALLOWING FOR A FOCUS OF SHOWER
AND THUNDERSTORM DEVELOPMENT ALONG NORTHERN KENTUCKY ON MONDAY AND
TUESDAY.
THROUGH THE REST OF THE EXTENDED...THE PATTERN IN PLACE WILL BE
FAVORABLE FOR MCS/S IN THIS NORTHWEST FLOW. THIS HOLDS TRUE
THROUGH TUESDAY AND THURSDAY PERIOD. HAVE KEPT THE SUGGESTED POPS
INHERITED BY THE SUPER BLEND WITH INSTABILITY AND MOISTURE IN
PLACE...THIS SEEMS LIKELY ACROSS EASTERN KENTUCKY...ESPECIALLY
WITH THE INCONSISTENCY IN THE GFS AND EURO. BY THE WEDNESDAY
EVENING AND WEDNESDAY NIGHT PERIOD...A BETTER COMPLEX IS SEEMS
POISED TO MOVE INTO THE AREA. HOWEVER...AS STATED EARLIER...THE GFS
AND EURO HAVE BEEN INCONSISTENT WITH THE TRACK AND TIMING THIS
LATE IN THE EXTENDED AS RECENT RUNS HAVE THE UPPER TROUGH PUSHING
FURTHER SOUTH AS WELL AS THE SURFACE GRADIENT. OVERALL...THE DAY
5...6 AND 7 PERIOD SEEMS QUITE ACTIVE AND WILL KEEP THE HIGH
CHANCE POPS ADVERTISED BY THE SUPER BLEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 220 PM EDT SAT AUG 1 2015
HIGH PRESSURE WILL KEEP VFR CONDITIONS IN THE TAF FORECAST FOR
ALL SITES THROUGH THE PERIOD. SOME CU IN THE MVFR RANGE IS
EXPECTED THROUGH ABOUT 21Z BEFORE DISSIPATING...WITH CU POSSIBLY
AGAIN DEVELOPING BEFORE THE END OF THE PERIOD. COME MID AND HIGH
DEBRIS CLOUDS WILL ALSO PASS BY FROM TIME TO TIME. OUTSIDE OF THE
OFFICIAL TAF SITES...PATCHY FOG AGAIN WILL BE FOUND IN THE LOWER
ELEVATIONS DURING THE 6Z TO 13Z PERIOD...PERHAPS BECOMING LOCALLY
DENSE OR IFR CONDITIONS THERE FOR A BRIEF TIME. WINDS THROUGH THE
PERIOD WILL BE LIGHT AND VARIABLE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JP
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...JP
AREA FORECAST DISCUSSION
NWS CARIBOU ME
617 PM EDT SAT AUG 1 2015
.SYNOPSIS...
A SERIES OF UPPER LEVEL DISTURBANCES WILL MOVE ACROSS THE REGION
THIS WEEKEND BRINGING SHOWERS AND THUNDERSTORMS. A COLD FRONT IS
EXPECTED TO APPROACH THE REGION MONDAY NIGHT AND MOVE ACROSS THE
AREA ON TUESDAY.
&&
.NEAR TERM /THROUGH SUNDAY/...
615 PM UPDATE...
TSTMS ARE PRETTY MUCH OUT OF CWA THIS EVNG WITH JUST AN ISOLD
SHOWER SKIRTING ACRS THE CROWN OF MAINE IN ADVANCE OF WK S/WV.
NEXT BATCH OF PCPN OVR SRN QUEBEC ON TAP TO MV INTO CWA WL LKLY
DIMINISH WITH LOSS OF DIURNAL HTG PER LATEST HRRR AND NAM. EXPECT
JUST AN ISOLD SHOWER TO AFFECT WRN ZONES BY DAYBREAK AT THE MOST.
WINDS WL LKLY RMN UP HIGH ENUF TO PREVENT MUCH IN THE WAY OF
PATCHY FOG OVRNGT THO THIS IS SOMETHING THAT MAY NEED TO BE ADDED
IN LATER. HV ADJUSTED HRLY T/TD VALUES IN WAKE OF AREA OF
CONVECTION. NO CHGS NEEDED TO MIN TEMPS TONIGHT AT THIS POINT.
PREV DISCUSSION BLO...
THUNDERSTORMS ARE ONGOING THIS AFTERNOON AS AN UPPER SHORTWAVE
TRAVERSES ACROSS THE REGION. THIS ACTIVITY WILL QUICKLY MOVE INTO
NEW BRUNSWICK BY THIS EVENING AS THE SHORTWAVE CONTINUES TO PUSH
EAST. THEREAFTER, SKIES WILL CLEAR OUT AS SHORTWAVE RIDGING
BRIEFLY BUILDS INTO THE AREA. OVERNIGHT LOWS WILL BE IN THE MID TO
UPPER 50S IN MOST LOCATIONS.
FOR TOMORROW...ANOTHER UPPER SHORTWAVE WILL TREK ACROSS THE
REGION. THIS WILL BRING SCATTERED SHOWERS AND THUNDERSTORMS,
MAINLY TO NORTHERN PORTIONS OF OUR AREA. HIGHS WILL BE IN THE MID
70S NORTH, TO AROUND 80 ACROSS INTERIOR DOWNEAST.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
CWA WL BE IN TRANSITION FM HIPRES TO APPCHG LOPRES ON SUN NGT.
LOPRES WL MV INTO ERN QUEBEC WITH TRAILING CDFNT BACK TO THE WEST BY
12Z MON. 12Z MODELS DIFFER ON PLACEMENT OF FRONT BY THIS TIME WITH
GFS FURTHER WEST THAN NAM/CMC. H5 FLOW BCMS ZONAL AT THE START OF
THE SHORT TERM WITH BRIEF RIDGING THRU MOST OF THE OVRNGT. RIDGE WL
DEFLECT S/WVS OFF TO THE NW WITH ONLY ISOLD SHRA OR THUNDER EXPECTED
ACRS THE FAR NORTH TWD DAYBREAK AS UPR TROF AND ASSOC FRONT APPCHS.
MIN TEMPS SUN NGT WL BE FAIRLY UNIFORM ACRS CWA IN THE U50S. SRLY
FLOW ACRS DOWNEAST WL KEEP TEMPS WARM AND CLDY SKIES ACRS THE NW WL
KEEP TEMPS FM DROPPING OFF TOO MUCH DRG THE NIGHT. ELEVATED
INSTABILITY EXPECTED TO BE PRESENT THRU 04Z ACRS THE CROWN OF MAINE.
AIRMASS WL LKLY DESTABILIZE AHD OF NEXT APPCHG FRONT ON MONDAY.
TEMPS WL WARM INTO THE L/M 80S AS TEMPS SOAR ABV 20C. BUFKIT SNDGS
INDICATE 500-1000 J/KG PER GFS FOR MON AFTN WHILE NAM IS ABOUT 2X
AS HIGH. CYCLONICALLY-CURVED HODOGRAPH ALONG WITH STRONG BULK
SHEAR VALUES AND STRONG MID-LVL LAPSE RATES WL LKLY SPELL THE NEXT
SVR THREAT LATE AFTN INTO THE EVNG.
FROPA OCCURS SOMETIME TUE MRNG WITH CONTD SHOWERS AND POSSIBLY
TSTORMS AHD OF UPR LVL TROF. MAXES ON TUE WL BE RIGHT ARND NORMAL
AS SHOWERS AND CLOUDS PREVENT MUCH RISE IN TEMPS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE MAIN CONCERN FOR THE EXTENDED FORECAST PERIOD IS A SERIES OF
WEAK UPPER LEVEL SHORTWAVES THAT ARE PROGGED TO PROPAGATE EWD
ACROSS MAINE. EACH WAVE COULD PRODUCE ISOLD/SCTD SHOWERS AND
STORMS ACROSS THE NORTHERN TWO THIRDS OF OUR CWA...WITH THE BEST
CHANCE OCCURRING ON WEDNESDAY. THIS ACTIVITY WILL HAVE A STRONG
DIURNAL COMPONENT...SO WE ARE EXPECTING MOST OF THE PRECIP TO FALL
DURING THE DAYTIME HOURS. TEMPERATURES WILL BE COOLER WITH BELOW
NORMAL TEMPS. HIGHS WILL GENERALLY RANGE FROM THE UPPER 60S TO MID
70S.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
NEAR TERM: MAINLY VFR EXPECTED AFTER 00Z SUNDAY AS SKIES WILL
CLEAR OUT. LOCAL IFR WILL BE POSSIBLE UNTIL THEN IN SCATTERED
SHOWERS AND THUNDERSTORMS. VFR WILL PREVAIL 18Z SUNDAY, THEN LOCAL
MVFR IS POSSIBLE AT THE NORTHERN TERMINALS AS SCATTERED SHOWERS
AND THUNDERSTORMS DEVELOP DURING THE AFTERNOON.
SHORT TERM: VFR EXPECTED THROUGH MONDAY MORNING BEFORE LINE OF
SHOWERS AND THUNDERSTORMS AHEAD OF FRONT BRINGS MVFR AND POSSIBLY
IFR CONDITIONS TO TERMINALS LATE MON AFTERNOON CONTINUING THROUGH
THE DAY ON TUESDAY. VFR AND OCCASIONAL MVFR CAN BE EXPECTED
THROUGH THE MIDDLE OF THE WEEK AS UPPER LEVEL DISTURBANCE MOVES
THROUGH THEN VFR AFTER.
&&
.MARINE...
NEAR TERM: NO HEADLINES WILL BE NEEDED ACROSS THE WATERS TONIGHT
AND SUNDAY. WINDS WILL REMAIN AT 10 TO 15 KT AND WAVES AROUND 3
FEET THROUGH THE PERIOD.
SHORT TERM: WINDS/SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA THROUGH MONDAY NIGHT. SOUTHERLY WINDS AHEAD OF FRONT MAY
ALLOW SEAS TO BUILD ABOVE 5 FEET ON TUESDAY.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...FARRAR/HASTINGS
SHORT TERM...FARRAR
LONG TERM...BERDES
AVIATION...FARRAR/HASTINGS/FARRAR
MARINE...FARRAR/HASTINGS/FARRAR
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1206 PM EDT SAT AUG 1 2015
.SYNOPSIS...
DRY WEATHER AND SEASONAL TEMPERATURES WILL CONTINUE THROUGH
SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
WITH NOON UPDATE...UPDATED WINDS AND SKY COVER THROUGH THE
AFTERNOON/EVENING HOURS. STILL DEBATED ADDING SOME PRECIPITATION
INTO THE FORECAST ACROSS THE NORTH...BUT WITH MOST RECENT RUNS OF
THE HRRR SHOWING LESS PRECIPITATION THAN EARLIER RUNS AND PLENTY
OF DRY AIR BELOW 5000 FEET...WITH GO WITH A DRY FORECAST. A BRIEF
SPRINKLE WILL NOT REMAIN OUT OF THE QUESTION. NEAR AVERAGE
TEMPERATURES AND LOW DEWPOINTS ARE EXPECTED TODAY. WEAK SURFACE
HIGH PRESSURE WILL BUILD OVERHEAD TOWARD EVENING...WITH SKIES
CLEARING AND SOME VALLEY FOG POSSIBLE.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ANOTHER DRY AND SEASONABLE DAY SUNDAY...THEN A DEEPENING AREA OF
LOW PRESSURE ALOFT ACROSS THE GREAT LAKES WILL BRING A STRONGER
SHORTWAVE TO THE REGION LATER SUNDAY NIGHT. THIS WILL BRING
INCREASING SHOWER CHANCES INTO MONDAY. UPPER TROUGH AND A COLD
FRONT WILL CROSS BY MONDAY NIGHT WITH FRONT STALLING SOUTH OF THE
MASON DIXON LINE. ANOTHER HARD TO TIME FAST MOVING WAVE WILL MOVE
ALONG THE FRONT SOMETIME TUESDAY...AND HAVE GONE WITH CHANCE POPS
ESPECIALLY ACROSS THE SOUTH CLOSER TO FRONT. A GRADUAL COOLING
TREND BY TUESDAY WITH TEMPERATURES MOVING A BIT BELOW AVERAGE.
&&
.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
UPPER TROUGH WILL REMAIN SITUATED OVER THE EASTERN US THROUGH THE
LONG TERM WITH SEVERAL SHORTWAVES PROGGED TO HELP DEEPEN IT THROUGH
THE PERIOD. THIS WILL LIKELY KEEP TEMPERATURES JUST SLIGHTLY COOLER
THAN SEASONAL AVERAGES. BY LATE IN THE WEEK...MODEL GUIDANCE
SUGGESTS A SURFACE WAVE COULD DEVELOP AND LIFT ACROSS THE OHIO
VALLEY LATE. BUT...WITH RUN TO RUN INCONSISTENCY OPTED TO STAY
CLOSER TO WPC GUIDANCE VALUES...WHICH KEEP CHANCE POPS THROUGH THE
BEGINNING OF NEXT WEEKEND.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
GENERAL VFR WILL CONTINUE INTO SUNDAY WITH DRY SURFACE HIGH
PRESSURE SUPPRESSING PRECIP UNDER NW FLOW ALOFT.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...
RESTRICTION POTENTIAL WILL INCREASE WITH THE APPROACH AND PASSAGE
OF A MONDAY COLD FRONT.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
324 PM EDT SAT AUG 1 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 323 PM EDT SAT AUG 1 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALOFT OVER
THE GREAT LKS BTWN CLOSED UPR LO OVER HUDSON BAY AND RDG ACROSS THE
WRN CONUS. THE 12Z INL/GRB RAOBS SHOW A RELATIVELY DRY...CAPPED
ENVIRONMENT...SO THE DIURNAL CU THAT POPPED UP HAVE BEEN FAIRLY
SHALLOW WITH LARGE SCALE DEEP LYR QVECTOR DVGC/SUBSIDENCE
DOMINATING. THE ONLY EXCEPTION IS OVER THE SE CWA E OF ESCANABA...
WHERE RADAR INDICATES A FEW SHOWERS HAVE POPPED UP IN AN AREA CLOSER
TO SOME DEEPER MSTR/LESS CAPPED ENVIRONMENT SHOWN ON THE 12Z APX
RAOB AND WHERE LLVL CNVGC HAS BEEN ENHANCED BY LK BREEZE CNVGC.
LOOKING UPSTREAM...A SHRTWV IS DROPPING SEWD THRU MANITOBA. THERE IS
A BAND OF CLDS AND A FEW SHOWERS ASSOCIATED WITH AXIS OF HIER H7 RH
IN AREA OF DPVA/H7-5 QVECTOR CNVGC MOVING INTO NW ONTARIO AHEAD OF
THIS FEATURE. FARTHER AWAY...ANOTHER SHRTWV TOPPING WRN RDG IS
MOVING ESEWD THRU SASKATCHEWAN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON SHOWER/TS CHANCES
ASSOCIATED MAINLY WITH THE TWO SHRTWVS NOTED ABOVE.
TNGT...FIRST SHRTWV OVER MANITOBA IS FCST TO SLIDE SEWD THRU NW
ONTARIO...WITH SHARPER DPVA/DEEP LYR QVECTOR CNVGC REMAINING TO THE
N. ALTHOUGH THE LLVL FLOW IS FCST TO BACK TOWARD THE WSW TO THE S OF
THE TRACK OF THIS DISTURBANCE...GUIDANCE INDICATES THE MOST
IMPRESSIVE MSTR CNVGC WL REMAIN TO THE S IN WI...JUST BRUSHING THE
BORDER. WITH THE DISCONNECT BTWN THIS MOISTENING TO THE S AND THE
MORE IMPRESSIVE DYNAMIC SUPPORT REMAINING TO THE N...SUSPECT PCPN
OVER MUCH OF UPR MI WL BE RATHER LIMITED BTWN AXES OF HIER POPS TO
THE N AND ALONG THE SRN CWA/WI. INCRSG PWAT AND WSW FLOW WL TEND TO
LIMIT THE DIURNAL TEMP DROP.
SUN...DPVA/DEEP LYR QVECTOR CNVGC IN ADVANCE OF SHRTWV NOW MOVING
THRU SASKATCHEWAN IS FCST TO ARRIVE OVER SLOW MOVING...WEAKENING
COLD FNT THAT WL BE DROPPING SLOWLY SE ACRS THE CWA ATTENDANT TO
FIRST DISTURBANCE EXITING INTO QUEBEC. SOME OF THE MODELS...
ESPECIALLY THE 12Z GFS...ALSO HINT AT THE POTENTIAL FOR SOME
ENHANCED UPR DVGC IN RRQ OF EXITING H3 JET MAX SUPPORTING THE FIRST
DISTURBANCE AND EXIT REGION OF INCOMING JET STREAK ASSOCIATED WITH
2ND SHRTWV. SINCE THIS FORCING WL BE ARRIVING DURING PERIOD OF
DAYTIME HEATING...SUSPECT SHOWERS/TS WL BECOME MORE NUMEROUS. SO
TENDED TO BUMP POPS UP INTO THE LIKELY RANGE OVER MUCH OF THE CWA.
WITH INCRSG H85-5 RH...THERE ARE CONCERNS ABOUT HOW MORE CLDS WL
IMPACT SFC DESTABILIZATION. THE 12Z NAM SHOWS MUCAPE AS HI AS 2500-
3000 J/KG OVER THE SCENTRAL UNDER AREA OF STEEP H7-5 LAPSE RATES
APRCHG 8C/KM PER THE THE 12Z GFS. ALTHOUGH MOST OF THE GUIDANCE
SUGGESTS THE BULK OF THE PCPN WL FALL ON THE COOL SIDE OF THE FNT
AND THERE WL BE A GOOD DEAL OF CLD COVER THAT SUG THE NAM FCST
MUCAPE IS TOO HI...TS THAT FORM ALONG AND AHEAD OF THE FNT
ESPECIALLY OVER THE SCENTRAL COULD TURN STRONG TO SEVERE WITH DEEP
LYR SHEAR NEAR 40 KTS. IN FACT...THE NEW SPC OUTLOOK FOR SUN AS
SHIFTED THE NRN EDGE OF MARGINAL RISK FOR SVR STORMS AS FAR N AS SRN
MNM COUNTY. POPS WL DIMINISH FM THE NW BY MID/LATE AFTN FOLLOWING
ARRIVAL OF SUBSIDENCE/MID LVL DRYING FOLLOWING THE SHRTWV.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 317 PM EDT SAT AUG 1 2015
IMPACTS...COOLER TEMPERATURES AND GREATER MOISTURE WILL HAVE A
POSITIVE IMPACT ON FIRE WEATHER...AT LEAST SOMEWHAT LOWERING
CONCERNS.
A TROUGH/COLD FRONT AND ASSOCIATED PRECIPITATION WILL BE MOSTLY OUT
OF THE AREA BY 00Z MON AS THE UPPER LOW THAT HAS BEEN SITTING OVER
HUDSON BAY MOVES S INTO ONTARIO. AS THE LOW MOVES FROM EXTREME NRN
ONTARIO AT 00Z MON TO THE ONTARIO/QUEBEC BORDER E OF LAKE SUPERIOR
BY 00Z WED...THE CORE OF COLDEST AIR (850MB TEMPS OF 3-4C) WILL
SLIDE INTO THE CWA. THE COLDER MID LEVELS WILL ALLOW FOR CONVECTIVE
SHOWERS MON THROUGH TUE AS LOW LEVEL MOISTURE WILL BE INCREASED AND
SUBTLE SHORTWAVES WILL BE MOVING THROUGH. SFC TEMPS WILL BE 7-10
DEGREES BELOW NORMAL WITH HIGHS IN THE MID 60S TO MID 70S. LOWS WILL
BE FROM THE MID 40S INLAND TO THE MID 50S NEAR THE GREAT LAKES.
TUE NIGHT THROUGH WED NIGHT WILL SEE A SFC RIDGE MOVE
OVERHEAD...WITH NO PRECIP EXPECTED. TEMPS MAY BE A DEGREE OR TWO
WARMER THAN TUE WITH HIGHS IN THE UPPER 60S TO LOW 70S. THERE WILL
STILL BE ENOUGH MOISTURE TUE NIGHT TO KEEP TEMPS FROM FALLING INTO
THE 30S AND WED NIGHT MAY SEE INCREASING CLOUD COVER AND RETURN FLOW
TO KEEP TEMPS FROM FALLING TO CONCERNING LEVELS.
THE REST OF THE PERIOD THU THROUGH SAT IS QUITE A BIT MORE UNCERTAIN
IN EXACT DETAILS AS CONDITIONS LOOK TO BE DRIVEN LARGELY BY
SHORTWAVES. SLIGHT CHANCES OF PRECIP EACH DAY AS GIVEN BY CONSENSUS
GUIDANCE IS REASONABLE...SO WILL LEAVE THAT IN THE FORECAST.
ALSO...TEMPERATURES LOOK TO REMAIN BELOW NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 148 PM EDT SAT AUG 1 2015
GUSTY WINDS THIS AFTN WL DIMINISH THIS EVNG WITH LOSS OF DAYTIME
HEATING/MIXING. ALTHOUGH A PASSING DISTURBANCE MAY BRING SOME
-SHRA TO UPR MI LATE TNGT...LLVL DRY AIR INDICATES VFR CONDITIONS WL
PREDOMINATE EVEN IF ANY OF THE SHOWERS PASSES OVER ONE OF THE TAF
SITES. THERE WL ALSO BE SOME MARGINAL LLWS OVERNGT WITH A
STRENGTHENING WSW FLOW ABOVE NEAR SFC STABLE LYR. THE APPROACH OF A
STRONGER DISTURBANCE ON SUN WL BRING A BETTER CHC FOR SOME SHOWERS
AND PERHAPS A TS...BUT VFR CONDITIONS SHOULD STILL PREDOMINATE WITH
LINGERING LLVL DRY AIR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 323 PM EDT SAT AUG 1 2015
A LOW SPINNING OVER SOUTHERN HUDSON BAY WILL SWEEP A PAIR OF TROFS
ACROSS LAKE SUPERIOR TONIGHT AND SUN. WINDS WILL GENERALLY BE IN THE
10-20KT RANGE. HI PRES FROM THE CANADIAN PRAIRIES WILL MOVE OVER THE
REGION THROUGH MOST OF NEXT WEEK...KEEPING WINDS UNDER 20 KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...KC
UPDATED FOR THE NEW 18Z AVIATION FORECAST DISCUSSION BELOW.
UPDATE ISSUED AT 845 AM CDT SAT AUG 1 2015
CLEAR SKIES COVERED THE NORTHLAND EARLY THIS MORNING WITH A LITTLE
MID LEVEL CLOUD NEAR OR JUST SOUTH OF THE BRAINERD LAKES REGION.
AN EARLY LOOK AT SOME OF THE HIGH RES CAMS SHOWED AN AREA OF
SHOWERS DEVELOPING NEAR AND JUST SOUTH OF HIGHWAY 2 IN MINNESOTA
LATE MORNING/EARLY AFTERNOON...THEN MOVING SOUTHEAST. THERE IS
SOME ACCAS OVER PORTIONS OF EASTERN NORTH DAKOTA AND MOST OF THOSE
MODELS INDICATE THAT IS NEAR WHERE THE SHOWERS WILL INITIALLY
FORM.
WE WILL NOT UPDATE TO INCLUDE SHOWERS AT THIS TIME. NOT ALL MODELS
INDICATE THESE SHOWERS WILL DEVELOP AND THE LATEST SPC HRRR OVER
THE PAST FEW RUNS HAVE DELAYED THE ARRIVAL OF THESE SHOWERS AND
HAVE CUT BACK ON THE COVERAGE. WE WILL MONITOR AND UPDATE AS
NEEDED.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 339 AM CDT SAT AUG 1 2015
AT 400 AM...SKIES WERE MOSTLY CLEAR ACROSS THE NORTHLAND.
TEMPERATURES RANGED FROM THE UPPER 40S TO THE MIDDLE 50S. A FEW
LOCATIONS NEAR LAKE SUPERIOR WERE IN THE LOWER 60S WITH LIGHT
WINDS.
THE FOCUS FOR TODAY THROUGH SUNDAY WILL BE TRYING TO RESOLVE
VARIOUS PRECIPITATION EVENTS. THE SHOWERS THAT MOVED THROUGH THE
ARROWHEAD EARLIER THIS MORNING WERE FINALLY PUSHING OFF TO THE
SOUTHEAST ACROSS LAKE SUPERIOR. THE LATEST HIGH RESOLUTION
MODELS GENERALLY FAVOR A MOSTLY DRY FORECAST FOR THE AREA
TODAY...ALTHOUGH WE WILL CONTINUE TO CARRY A SMALL POP ACROSS THE
FAR NORTH AND FAR SOUTH/SW DURING THE AFTERNOON. THE BETTER CHANCE
FOR SHOWERS AND THUNDERSTORMS WILL ARRIVE TONIGHT...AS A WEAK AREA
OF LOW PRESSURE AND WARM FRONT MOVES SOUTHEASTWARD THROUGH CENTRAL
MN. THIS WEAK FEATURE WILL SET THE STAGE FOR THUNDERSTORMS...WITH
A COLD FRONT ACROSS THE INTERNATIONAL BORDER SETTING THE STAGE FOR
SHOWERS AND THUNDERSTORMS ACROSS THE NORTH.
IN TERMS OF SPECIFICS...TODAY SHOULD BE A GENERALLY DRY DAY. AGAIN
WE WILL CARRY SMALL POPS FAR NORTH AND SOUTH. HIGH TEMPERATURES
WILL GENERALLY BE AROUND 80 DEGREES WITH WEST WINDS.
TONIGHT...SHOWERS AND THUNDERSTORMS SHOULD INCREASE IN NUMBER...
ESPECIALLY ACROSS THE NORTH AND THE SOUTH. CENTRAL PORTIONS OF THE
CWA SHOULD SEE THE LEAST SHOWER AND THUNDERSTORM ACTIVITY. THINK
SOME OF THE STORMS IN THE SOUTH COULD BE STRONG OVERNIGHT...AND
THERE COULD BE A SEVERE THUNDERSTORM AS WELL. THE PRIMARY THREAT
WOULD BE SOUTH OF A BRAINERD TO HAYWARD LINE...WITH HAIL AND
STRONG WINDS BEING THE PRIMARY THREATS. OVERNIGHT LOWS WILL RANGE
FROM THE 50S TO LOWER 60S.
ON SUNDAY...WE SHOULD CONTINUE TO SEE SCATTERED SHOWERS AND
THUNDERSTORMS...ESPECIALLY ACROSS THE ARROWHEAD...TWIN PORTS AND
NORTHWESTERN WISCONSIN. LESSER CHANCES ARE EXPECTED FURTHER WEST.
HIGHS WILL BE A LITTLE COOLER ON SUNDAY...WITH HIGHS RANGING FROM
THE LOWER 70S IN THE ARROWHEAD TO AROUND 80 FURTHER SOUTH.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 339 AM CDT SAT AUG 1 2015
OVERALL A SEASONAL PATTERN FOR EARLY AUGUST WITH HIGH TEMPERATURES
PERHAPS ON THE COOL SIDE OF NORMAL FOR A FEW DAYS...A WELCOME RELIEF
TO THE PAST FEW WEEKS WHICH HAVE BEEN WELL ABOVE NORMAL. SOME
CHANCES FOR PRECIPITATION OVER THE MINNESOTA ARROWHEAD MONDAY AND
PERHAPS TUESDAY...BUT OTHERWISE DRY FOR MOST THE NORTHLAND THROUGH
WEDNESDAY. LATER IN THE WEEK MORE WIDESPREAD PRECIP CHANCES...BUT
NOT VERY CONFIDENT GIVEN MODEL VARIABILITY AT THIS TIMEFRAME.
MON/TUES...STACKED LOW MEANDERING OVER HUDSON BAY WILL EVENTUALLY
DRIFT SOUTHEAST INTO NORTHERN ONTARIO...WITH WIDESPREAD WEAK LARGE-
SCALE LIFT AROUND IT THAT MAY RESULT IN A FEW SHOWERS OR STORMS
EDGING INTO FAR NORTHEAST MINNESOTA. THIS THREAT WILL BE HIGHEST ON
MONDAY AFTERNOON WHEN GFS/GEFS/ECMWF ALL DEPICT SOME WEAK LIFT AT
LOW/MID LEVELS AND ENOUGH LOW LEVEL MOISTURE TO RESULT IN A FEW
SHOWERS. OTHERWISE COOL AIR ADVECTING IN FROM THE NORTHWEST WILL
RESULT IN HIGHS AT OR SLIGHTLY BELOW NORMAL...IN THE LOW TO MID 70S.
OVERNIGHT LOWS SUN/MON/TUES NIGHT COULD DIP INTO THE UPPER 40S
ACROSS LOCATIONS AWAY FROM LAKE SUPERIOR DEPENDING ON CLOUD COVER.
WED...A LONGWAVE TROUGH OVER THE NORTHERN HIGH PLAINS DRIFTS
EASTWARD INTO THE UPPER MIDWEST RESULTING IN AT LEAST SOME WEAK WARM
AIR ADVECTION AT LOW LEVELS. INCREASING CLOUDS LATE...DEPENDING ON
HOW UPSTREAM CONVECTION EVOLVES. HIGHS A FEW DEGREES WARMER...BUT
STILL IN THE LOW TO MID 70S RANGE. LOWS WED NIGHT WARMER DUE TO
CLOUD COVER AND WEAK WAA...IN THE LOW TO MID 50S.
THURS/FRI/SAT...A SFC LOW WILL DEVELOP ACROSS THE CENTRAL/NORTHERN
PLAINS IN RESPONSE TO SHORTWAVE TROUGH CROSSING OVER THE NORTHERN
ROCKIES DURING THE MIDDLE OF THE WEEK...BUT HOW IT EVOLVES AS IT
MOVES EAST IS UNCERTAIN. ECMWF...WHICH HAS BEEN A BIT MORE
CONSISTENT RUN-TO-RUN...BRINGS THIS SYSTEM TOWARDS THE UPPER MIDWEST
WHILE THE GFS DEPICTS A COLD FRONT DROPPING SOUTH OUT OF CANADA
RESULTING IN A DRIER SCENARIO FOR THE NORTHLAND AS PRECIP IS FORCED
SOUTH. USED A BLEND OF AVAILABLE GUIDANCE WHICH RESULTED IN SLIGHT
CHANCE TO CHANCE POPS DURING THIS PERIOD. SHOULD THE ECMWF SCENARIO
PLAY OUT IT LOOKS LIKE THIS WILL BE A WIDESPREAD LIGHT TO MODERATE
RAIN EVENT DUE TO LITTLE INSTABILITY ALOFT. TEMPS SEASONABLE IN MOST
SCENERIES...AGAIN IN THE LOW TO MID 70S WITH LOWS MILD IN THE 50S TO
LOW 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1242 PM CDT SAT AUG 1 2015
THE VFR CONDITIONS ACROSS NE MINNESOTA AND NW WISCONSIN SHOULD
CONTINUE THROUGH THIS AFTERNOON. THERE IS A POSSIBILITY OF -SHRA
AND -TSRA THIS EVENING INTO SUNDAY MORNING. THE HIGHEST CHANCES
FOR THUNDER WILL BE FOR KBRD AND KHYR THIS EVENING TO AROUND
MIDNIGHT...SO FELT CONFIDENT ENOUGH TO MAINTAIN A PERIOD OF VCTS
FOR THOSE AIRPORTS. LESS CONFIDENT ABOUT THUNDER FOR
KINL/KHIB/KDLH...BUT SHOWERS WILL LIKELY DROP SOUTH OUT OF CANADA
LATE THIS EVENING INTO SUNDAY MORNING WITH THE PASSAGE OF A COLD
FRONT. THERE COULD BE ISOLATED THUNDER WITHIN THOSE SHOWERS. THERE
COULD BE IFR/MVFR CLOUD COVER BEHIND THE COLD FRONT EARLY
SUNDAY...BUT NOT CONFIDENT ENOUGH YET TO INCLUDE THIS IN THE
FORECASTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 81 60 80 55 / 10 40 40 0
INL 79 51 76 50 / 20 50 30 10
BRD 85 58 82 54 / 30 30 20 0
HYR 82 57 81 52 / 10 40 40 0
ASX 81 59 81 55 / 0 40 50 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
UPDATE...GROCHOCINSKI
SHORT TERM...DAP
LONG TERM...JJM
AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1239 PM CDT SAT AUG 1 2015
.SHORT TERM: (THROUGH TONIGHT)
ISSUED AT 340 AM CDT SAT AUG 1 2015
SCATTERED THUNDERSTORMS HAVE RECENTLY DEVELOPED OVER NORTHEAST
MISSOURI AND WEST CENTRAL ILLINOIS IN AN SMALL AREA OF LOW LEVEL
MOISTURE CONVERGENCE. RECENT RUNS OF THE RAP SHOW THIS FORCING
ERODING AROUND 12Z. ATMOSPHERE WILL BECOME UNSTABLE AGAIN THIS
AFTERNOON...HOWEVER THERE WILL BE LITTLE IN THE WAY OF FORCING FOR
IT TO ACT ON. HAVE KEPT CHANCE POPS OVER NORTHEAST MISSOURI AND
WEST CENTRAL ILLINOIS...PARTICULARLY OVERNIGHT AS A SHORTWAVE TROUGH
WILL MOVE THROUGH THE UPPER MIDWEST WHICH WILL LIKELY PUSH A MCS
ALONG A FRONTAL BOUNDARY OVER IOWA INTO INTO THE NORTHERN CWA.
SHOULD BE ANOTHER WARM DAY ACROSS THE AREA WITH 850MB TEMPERATURES
BETWEEN 18-20C. HIGH TEMPERATURES SHOULD CLIMB BACK INTO THE LOW-
MID 90S WITH MIXING UP TO 850MB.
BRITT
.LONG TERM: (SUNDAY THROUGH FRIDAY)
ISSUED AT 340 AM CDT SAT AUG 1 2015
(SUNDAY AND MONDAY)
WILL CONTINUE THE CHANCE OF THUNDERSTORMS ON SUNDAY AS THE COLD
FRONT MOVES DOWN INTO THE AREA. CHANCES WILL BE LOWER ON SUNDAY
NIGHT AND MONDAY AS CONVERGENCE WEAKENS ALONG THE FRONT AS IT MOVES
TO THE SOUTHWEST UNDER NORTHWESTERLY FLOW ALOFT. BOTH DAYS WILL
CONTINUE TO BE WARM WITH MOS TEMPERATURES IN THE LOW-MID 90S AND
850MB TEMPERATURES REMAINING NEAR 20C.
(TUESDAY THROUGH FRIDAY)
IT STILL LOOK LIKE MID TO LATE NEXT WEEK WILL BE UNSETTLED WITH A
CONTINUED CHANCE OF SHOWERS AND THUNDERSTORMS IN NORTHWEST FLOW
ALOFT. BEST CHANCE WILL BE TUESDAY INTO WEDNESDAY WHEN BOTH THE GFS
AND ECMWF SHOW A NOTABLE TROUGH MOVING THROUGH MISSOURI AND
ILLINOIS. TEMPERATURES WILL FALL BACK BELOW NORMAL AS 850MB
TEMPERATURES ARE FORECAST TO BE AROUND 15C.
BRITT
&&
.AVIATION: (FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1231 PM CDT SAT AUG 1 2015
SPECIFICS FOR KUIN: INITIALLY LIGHT/VARIABLE WINDS WILL BECOME
SOUTHERLY THEN TURN SOUTHWESTERLY LATE IN THE TAF PERIOD. A
DISTURBANCE MOVING THROUGH IA IS EXPECTED TO SUPPORT A
THUNDERSTORM CLUSTER IN SOUTHERN IA OVERNIGHT. IF THE THUNDERSTORM
COMPLEX DEVELOPS, THEN SH/TS COULD REACH KUIN AFTER 02/06Z.
SPECIFICS FOR KCOU: INITIALLY LIGHT/VARIABLE WINDS WILL BECOME
SOUTHERLY THEN TURN SOUTHWESTERLY LATE IN THE TAF PERIOD AROUND
THE BACK SIDE OF A DEPARTING HIGH PRESSURE CENTER. SCATTERED
THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON INVOF A SURFACE BOUNDARY
WHICH WAS LOCATED ACROSS CENTRAL MO AT TAF ISSUANCE.
SPECIFICS FOR KSTL, KSUS, KCPS: INITIALLY LIGHT/VARIABLE WINDS
WILL BECOME SOUTHERLY THEN TURN SOUTHWESTERLY LATE IN THE TAF
PERIOD AFTER A HIGH PRESSURE CENTER HAS MOVED OFF TO THE
SOUTHEAST. A PERIOD OF LIGHT TO NEARLY CALM WINDS MAY OCCUR
OVERNIGHT AT SOME LOCATIONS, ESPECIALLY KSUS IN THE RIVER VALLEY.
THE REMNANTS OF OVERNIGHT CONVECTION TO THE NORTH COULD REACH
KSTL/KSUS/KCPS AFTER 02/10Z HOWEVER CONFIDENCE IS TOO LOW TO
INTRODUCE VCTS IN THE TAF ATTM.
KANOFSKY
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1204 PM CDT Sat Aug 1 2015
...Short Term and 18Z Aviation Update...
.UPDATE...
Issued at 1200 PM CDT SAT AUG 1 2015
Have added a very low end chance for showers/thunderstorms across
central Missouri for this afternoon. A weak mid level impulse
will continue to move south across northern and northeastern
Missouri. Higher theta-e air is in place north of the Ozark
Plateau, and this combined with the mid level wave may be just
enough to kick off a couple of storms this afternoon. Activity
should be quite isolated and dissipate by sunset.
&&
.SHORT TERM...(Today and Tonight)
Issued at 254 AM CDT SAT AUG 1 2015
It is a fairly quiet morning across the Missouri Ozarks with
mostly clear skies and temperatures rather pleasant in the lower
to middle 60s. Today will be almost a carbon copy of yesterday`s
weather. Temperatures will be in the lower 90s. Humidity values
will still be rather low which means the heat index will be near
the actual air temperature. The latest HiRes short term models
like the HRRR and ARW show a very small potential for a spotty
shower developing this afternoon across the central Missouri area
down into the eastern Ozarks. Not sold on this potential at this
time and will only leave in a silent 10 percent chance for this
happening this afternoon.
.LONG TERM...(Sunday through Friday)
Issued at 254 AM CDT SAT AUG 1 2015
For the end of the weekend into early next week...The upper level
ridge remains west of the region with the center near the west
Texas area and the Missouri Ozarks region will be in a northwest
flow. Southerly winds at the surface will help bring back the
humidity and low level moisture. Temperatures will gradually
increase a degree or two each day with most areas reaching the
lower to middle 90s by Monday. The heat index will climb back into
the upper 90s to around 100 possible.
The weather pattern becomes somewhat unsettled by the middle of
next week. The first of a couple mid level shortwaves will move
across the top of the ridge over the western U.S. early next week.
This shortwave looks fairly decent and will impact the area on
Tuesday afternoon through Wednesday morning. The latest guidance has
moved up the timing a little bit since the previous runs. A weak
frontal boundary also will be stalled out across the Missouri
Ozarks for the middle of next week.
Another impulse will affect the area late Thursday into Friday.
Will not get too specific with timing this far out but it does
appear that there will be several rounds of thunderstorms possible
Tuesday through Friday for the area with a more active weather
pattern likely. Temperatures will also be slightly lower for the
middle and end of next week with highs in the middle to upper 80s.
Overall average rainfall will be in the 1 to 2 inch range for next
week.
&&
.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 1200 PM CDT SAT AUG 1 2015
VFR conditions are expected at all three terminals through the
next 24 hours. Winds will remain light and variable through the
night at all terminals, with southwesterly breezes developing by tomorrow
morning at JLN.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
UPDATE...Boxell
SHORT TERM...Griffin
LONG TERM...Griffin
AVIATION...Boxell
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1218 PM CDT SAT AUG 1 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM CDT SAT AUG 1 2015
A FAIRLY CHALLENGING FORECAST THIS MORNING AS CONVECTION HAS
CONTINUED AND ACTUALLY ENHANCED ACROSS PORTIONS OF THE LOCAL
FORECAST AREA OVERNIGHT. WITH THE TRAINING OF THIS CONVECTION OVER
THE SAME AREAS THE PAST FEW HOURS...COULD EVENTUALLY SEE SOME
MINOR FLOODING IN SPOTS IF ADDITIONAL ACTIVITY DEVELOPS.
IN THE MEANTIME...EXPECT AN UPPER LEVEL DISTURBANCE STRETCHING
FROM WESTERN SOUTH DAKOTA ACROSS THE LOCAL FORECAST AREA THIS
MORNING TO CONTINUE TO SPARK SHOWER AND THUNDERSTORM ACTIVITY
ACROSS THE LOCAL AREA THROUGH THE REMAINDER OF THE MORNING HOURS.
WHILE MOST GUIDANCE IS DOING A VERY POOR JOB WITH THE ONGOING
CONVECTION...08Z HRRR SEEMS FAIRLY WELL INITIALIZED...AND HAVE
LEANED TOWARDS THIS SOLUTION IN THE MORNING FORECAST. AS A
RESULT...EXPECT ONGOING CONVECTION TO CONTINUE ACROSS THE
NORTHEASTERN QUADRANT OF THE LOCAL AREA THROUGH THE LATE MORNING
HOURS BEFORE DISSIPATING...WITH THE FOCUS THEN TURNING TO THE
NEXT DISTURBANCE...WHICH IS EXPECTED TO DROP TOWARDS THE LOCAL
AREA FROM SOUTH DAKOTA DURING THE MID TO LATE AFTERNOON HOURS.
WHILE THE COVERAGE AND TIMING FROM THIS DISTURBANCE IS
STILL A BIT UNCERTAIN...SEVERAL MODELS ARE PICKING UP ON THIS
FEATURE...BRINING CONFIDENCE THAT AT LEAST THE NORTHERN PORTIONS
OF THE FORECAST AREA WILL SEE ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS THIS EVENING. WITH CAPE BUILDING AHEAD OF THIS
DISTURBANCE AND AMPLE SHEAR IN PLACE...IN PART DUE TO THE
PRESENCE OF A NEAR STATIONARY FRONTAL BOUNDARY ACROSS THIS
AREA...EXPECT THE POTENTIAL FOR A FEW STRONG TO MARGINALLY SEVERE
STORMS DEVELOPING DURING THE LATE AFTERNOON AND EVENING HOURS.
TEMPERATURE WISE...EXPECT ANOTHER SEASONABLY WARM AFTERNOON ACROSS
THE REGION WITH MOST LOCATIONS THAT ARE ABLE TO CLEAR OUT BY
AFTERNOON EXPECTED TO SEE TEMPERATURES CLIMB INTO THE LOWER TO
MIDDLES 90S...WITH THE BEST CHANCE FOR MORE WIDESPREAD CONVECTION
ALSO EXPECTED DURING THE LATE AFTERNOON THROUGH EARLY EVENING
HOURS. WITH THE RIGHT PARAMETERS IN PLACE...A FEW STRONG TO SEVERE
STORMS APPEAR LIKELY...ESPECIALLY FOR THE NORTHEASTERN PORTIONS OF
THE FORECAST AREA.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 403 AM CDT SAT AUG 1 2015
BIGGEST CONCERNS FOR THE FORECAST PERIOD...CHANCES OF THUNDERSTORMS
MONDAY NIGHT THROUGH TUESDAY NIGHT THEN AGAIN MID WEEK.
MODELS IN RELATIVE AGREEMENT WITH LARGE SCALE FEATURES SO WILL USE
BLEND. GENERALLY IN A NORTHWEST FLOW PATTERN THROUGH THE PERIOD.
THIS TYPE PATTERN TYPICALLY MAKES IT TOUGH TO FORECAST THE SPEED AND
STRENGTH OF SYSTEMS MOVING THROUGH. SO...CONFIDENCE IS NOT THE
HIGHEST IN TIMING...COVERAGE OR EVEN CHANCES OF RAIN UNTIL WE GET 12
TO 24 HOURS AWAY FROM ANY RAIN EVENT.
NONE THE LESS...THE MODELS ARE FAIRLY CONSISTENT IN FORECASTING A
NEARLY STATIONARY BOUNDARY OVER THE FORECAST AREA FROM MONDAY ON.
ALSO...MODELS SUGGEST A SHORT WAVE AND ASSOCIATED JET STREAK WILL
TOP THE RIDGE AND MOVE OVER AN AREA BETWEEN THE DAKOTAS AND KANSAS
ON MONDAY NIGHT OR TUESDAY. THUS...WILL LEAVE CHANCES FOR
THUNDERSTORMS IN FORECAST. IF STORMS DEVELOP THEY APPEAR TO HAVE
ENOUGH INSTABILITY AND WEAK SHEAR THAT A FEW COULD PRODUCE SOME NEAR
SEVERE HAIL STONES AND PERHAPS SOME GUSTY WINDS.
IN BETWEEN ANY STORMS THAT DEVELOP...DRY AND WARM WEATHER IS
EXPECTED. TEMPERATURES SHOULD BE NEAR NORMAL THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1216 PM CDT SAT AUG 1 2015
CURRENT SHOWER ACTIVITY IS WELL NORTH OF THE TERMINAL AREAS...BUT
IS ALLOWING FOR A FEW CLOUDS. THERE COULD BE SOME THUNDERSTORMS
DURING THE EVENING HOURS...BUT SHOULD BE FURTHER NORTH THAN
BEFORE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...ROSSI
LONG TERM...EDDY
AVIATION...JCB
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
332 PM MDT SAT AUG 1 2015
.SYNOPSIS...
AN ACTIVE MONSOON PATTERN IS EXPECTED TO PERSIST THROUGH THE
REMAINDER OF THE WEEKEND. SLOW-MOVING STORMS CAPABLE OF PRODUCING
TORRENTIAL RAINFALL AND FLASH FLOODING WILL REMAIN A CONCERN THIS
AFTERNOON AND EARLY TONIGHT AND AGAIN SUNDAY...ESPECIALLY IN NORTH
CENTRAL TO NORTHWEST PARTS OF NEW MEXICO. DRIER AND MORE STABLE
AIR WILL ATTEMPT TO WORK WEST BEGINNING MONDAY...SIGNIFICANTLY
LOWERING THE OVERALL COVERAGE OF STORMS AND FLASH FLOOD THREAT.
FEWER STORMS WILL TRANSLATE INTO A DAY TO DAY WARMING TREND NEXT
WEEK...AS WELL.
&&
.DISCUSSION...
SLOW-MOVING THUNDERSTORMS HAVE BEEN FOCUSED SQUARELY WITHIN THE
FLASH FLOOD WATCH THUS FAR...WITH TREMENDOUSLY IMPRESSIVE RAINFALL
RATES AS HIGH AS 3.3 INCHES PER HOUR AS MEASURED BY A PERSONAL
WEATHER STATION ON THE NORTHWEST SIDE OF SANTA FE. GENERALLY 1 TO
3 INCH PER HOUR RATES LIKELY WITH JUST ABOUT ANY WELL-DEVELOPED
STORM. MAY CONSIDER EXPANDING WATCH TO INCLUDE NE/EC AREAS
ALTHOUGH COVERAGE EAST OF THE CENTRAL MOUNTAIN CHAIN SHOULD BE
MORE ISOLATED TO SCATTERED. BUT RECENT RUNS OF THE HRRR CONTINUE
TO SUGGEST SMALL MCS-LIKE FEATURE ORGANIZING BETWEEN CLAYTON AND
CONCHAS DAM ROLLING TOWARD TUCUMCARI-LOGAN LATER THIS EVENING.
THIS WOULD ONE AREA OF CONCERN GIVEN VERY HEAVY RAIN PAST TWO
DAYS. WEAKNESS IN THE 500MB RIDGE NEAR THE NM/CO LINE ALSO A
PLAYER BUT VERY DIFFICULT TO TRACK BEYOND 12 HOURS.
OTHERWISE...WE`RE NOW MOVING INTO OUTFLOW BOUNDARY INTERACTION
TIME OF DAY FOR VALLEY LOCATIONS CENTRAL/WEST. AIR MASS PLENTY
MOIST WITH PRECIPITABLE WATER VALUES RANGING FROM 1.2 INCHES NW
TO 1.5 INCHES NEAR THE NM/TX LINE. A POCKET OF RELATIVELY LOWER
PWAT AIR /ONE 1 INCH OR SLIGHTLY LESS/ ANALYZED OVER THE LOWER RIO
GRANDE VALLEY TO UPPER GILA HAS KEPT COVERAGE A BIT LOWER THERE
BUT SUBTLE GRADIENTS.
GOING INTO SUNDAY...VERY LITTLE CHANGE TO OVERALL ORIENTATION OF
THE MONSOON PLUME BENEATH VERY WEAK STEERING CURRENTS. LEAST
FAVORED REGION WILL CONTINUE TO BE THE SOUTHEAST CORNER...WHILE
NC TO WC AREAS AGAIN FAVORED IN ADDITION TO THE SW THAT COULD SEE
A BUMP IN COVERAGE AS COMPARED TO TODAY.
THEREAFTER...WE HAVE BEGUN TO REFLECT A MARKED DECREASE IN STORM
COVERAGE MONDAY AND ESPECIALLY TUESDAY THROUGH THURSDAY. THIS AS
THE ANTICYCLONIC BELT OF WESTERLIES ELONGATES WEST-EAST AND SHIFTS
SLIGHTLY SOUTH PLACING THE AREA UNDER A DRIER WESTERLY FLOW
REGIME. THAT SAID...THE LAST DRYING EPISODE WAS POORLY HANDLED BY
VIRTUALLY ALL THE NWP MODELS AS THEY TEND TO DRY OUR MOIST
RESIDENT AIR MASS TOO QUICKLY. SO WE WILL PROCEED WITH A LITTLE
PRUDENCE...BUT DEFINITELY TRENDING FORECAST TOWARD MUCH FEWER
STORMS NEXT WEEK. IF THE MODELS ARE CORRECT WE WILL STRUGGLE TO
DEVELOP A STORM ANYWHERE BY MID- WEEK. THAT IN TURN WILL ALLOW FOR
A DAY TO DAY WARMING TREND. COULD SEE OUR NEXT BACKDOOR SURGE
THUR/FRI THEN WE START THE MOISTENING CYCLE OVER. KJ
&&
.FIRE WEATHER...
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL FOCUS ON
NORTHERN AND WESTERN NEW MEXICO TODAY AND SUNDAY...WITH FURTHER
DEVELOPMENT EAST OF THE CENTRAL MOUNTAIN CHAIN. STEERING FLOW FROM
THE UPPER LEVEL HIGH RECENTERING OVER THE SOUTHERN PORTION OF THE
STATE WILL STEER SLOW MOVING NORTH TO NORTHEAST STORMS ACROSS
NORTHWESTERN TO NORTH CENTRAL AREAS WHERE FLASH FLOODING WILL
CONTINUE TO BE A MAJOR CONCERN THROUGHOUT THE REMAINDER OF THE
WEEKEND.
LOOK FOR A DRIER AIR MASS TO FILTER INTO THE STATE MONDAY THROUGH
THURSDAY AS THE UPPER LEVEL HIGH OVER SOUTHERN NEW MEXICO SHIFTS
WESTWARD FILTERING IN DRIER AIR FROM THE PACIFIC. SHOWER AND
THUNDERSTORM ACTIVITY WILL DOWNTREND AS TEMPERATURES CREEP BACK TO
NORMAL/ABOVE NORMAL READINGS. EXPECT HAINES VALUES TO INCREASE TO
THE 5 AND 6 VALUES ALONG WITH DECREASING MIN RH VALUES. STORM
ACTIVITY WILL BE LIMITED TO HIGHER TERRAIN AREAS AND ADJACENT LOWER
ELEVATION AREAS. THE MOISTURE PLUME LOOKS TO MAKE ITS RETURN BY THE
FOLLOWING WEEKEND WITH AN INCREASE IN WETTING PRECIPITATION CHANCES
ACROSS THE WEST AND NORTH AS THE UPPER LEVEL HIGH STARTS TO SHIFT
EASTWARD.
EXPECT POOR VENT RATES ACROSS THE NORTH THE REMAINDER OF THE WEEKEND
WITH IMPROVEMENTS BY MONDAY THROUGH THURSDAY. MIN RH VALUES WILL
DROP INTO THE UPPER TEENS BY THE MIDWEEK BUT OVERNIGHT RECOVERIES
WILL REMAIN GOOD. 32
&&
.AVIATION...
18Z TAF CYCLE
SCATTERED TO NUMEROUS SHRA AND TSRA WILL FAVOR WESTERN AND
NORTHERN TERMINAL SITES TODAY AS THE UPPER LEVEL HIGH RECENTER OVER
THE SE PLAINS. EXPECT PEAK CONVECTIVE COVERAGE BETWEEN 18 AND
23Z. STORMS THAT DEVELOP ALONG THE SANGRE DE CRISTO MTNS WILL
DRIFT EASTWARD...IMPACTING KLVS. KTCC COULD SEE STORMS DEVELOP
AFTER 02Z. EXPECT PATCHY MVFR CIGS ALONG WITH OCCASIONAL MTN OBSCD
FOR SITES IMPACTED BY TSRA...ESPECIALLY KLVS AND KSAF. THERE COULD
BE A POSSIBILITY LINGERING MVFR/IFR CIGS ACROSS THE NORTH AND EAST
OVERNIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 62 87 60 89 / 60 40 40 10
DULCE........................... 51 78 50 81 / 70 60 60 20
CUBA............................ 54 78 53 81 / 60 70 60 20
GALLUP.......................... 56 82 54 85 / 50 40 40 20
EL MORRO........................ 54 78 52 81 / 70 60 40 20
GRANTS.......................... 56 81 54 83 / 50 50 40 20
QUEMADO......................... 55 78 54 83 / 50 40 40 20
GLENWOOD........................ 59 84 59 87 / 30 40 40 20
CHAMA........................... 50 75 49 77 / 70 70 70 30
LOS ALAMOS...................... 60 78 59 81 / 70 70 80 30
PECOS........................... 54 78 55 80 / 60 60 60 30
CERRO/QUESTA.................... 51 76 51 79 / 60 70 70 30
RED RIVER....................... 47 67 47 70 / 70 80 70 40
ANGEL FIRE...................... 49 70 48 73 / 70 80 70 40
TAOS............................ 52 79 52 81 / 50 50 50 20
MORA............................ 53 75 52 79 / 70 70 70 30
ESPANOLA........................ 57 82 57 86 / 50 50 60 20
SANTA FE........................ 58 79 58 82 / 50 50 50 30
SANTA FE AIRPORT................ 59 81 59 85 / 40 40 40 20
ALBUQUERQUE FOOTHILLS........... 63 84 63 87 / 40 40 40 20
ALBUQUERQUE HEIGHTS............. 66 85 67 88 / 30 30 30 10
ALBUQUERQUE VALLEY.............. 63 88 63 91 / 30 30 30 10
ALBUQUERQUE WEST MESA........... 63 88 64 91 / 30 30 30 10
LOS LUNAS....................... 64 87 63 91 / 40 30 20 10
RIO RANCHO...................... 64 87 64 90 / 40 40 30 10
SOCORRO......................... 64 90 63 92 / 30 30 30 20
SANDIA PARK/CEDAR CREST......... 59 81 59 84 / 40 40 50 20
TIJERAS......................... 60 82 59 85 / 40 40 50 20
MORIARTY/ESTANCIA............... 56 84 56 86 / 40 40 40 20
CLINES CORNERS.................. 58 80 58 83 / 40 30 50 20
GRAN QUIVIRA.................... 59 82 59 86 / 30 30 30 20
CARRIZOZO....................... 61 87 61 88 / 30 30 20 10
RUIDOSO......................... 57 79 57 80 / 40 40 30 30
CAPULIN......................... 57 81 57 83 / 50 40 50 20
RATON........................... 58 83 57 85 / 50 40 40 20
SPRINGER........................ 59 84 59 87 / 50 30 50 20
LAS VEGAS....................... 56 81 55 83 / 60 40 40 20
CLAYTON......................... 63 88 63 89 / 40 30 30 20
ROY............................. 61 85 60 86 / 50 30 40 20
CONCHAS......................... 67 91 67 94 / 50 20 30 20
SANTA ROSA...................... 64 90 65 93 / 50 20 40 20
TUCUMCARI....................... 67 93 66 95 / 40 20 30 20
CLOVIS.......................... 66 91 67 93 / 40 20 30 20
PORTALES........................ 67 92 68 94 / 40 20 30 20
FORT SUMNER..................... 67 92 67 95 / 30 20 20 20
ROSWELL......................... 69 96 69 97 / 20 20 20 20
PICACHO......................... 63 90 63 91 / 40 30 20 20
ELK............................. 62 83 61 84 / 40 50 30 30
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL MIDNIGHT MDT TONIGHT FOR THE FOLLOWING
ZONES... NMZ501>507-510>517.
&&
$$
41
AREA FORECAST DISCUSSION
NWS BISMARCK ND
554 PM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 543 PM CDT SAT AUG 1 2015
UNSTABLE AIRMASS REMAINS OVER SOUTHEAST NORTH DAKOTA.
HOWEVER...THERE HAS BEEN ENOUGH CIN TO PRECLUDE THUNDERSTORM
DEVELOPMENT FROM CU FIELD THAT DEVELOPED EARLIER THIS AFTERNOON.
CAPE REMAINS HIGH BUT SHEAR IS DECREASING. WILL KEEP A MENTION OF
THUNDER THROUGH 7 PM AS A FEW CU REMAIN OVER CENTRAL AND EASTERN
PORTIONS OF DICKEY/LAMOURE COUNTIES.
TO THE NORTHWEST...A LINE OF CU HAS DEVELOPED ALONG THE COLD FRONT
MOVING INTO NORTHWEST NORTH DAKOTA. SUFFICIENT BULK SHEAR ALONG
THE INTERNATIONAL BORDER BUT DEEP MOISTURE IS LACKING...ESPECIALLY
RIGHT ALONG AND BEHIND THE FRONT WITH MUCH DRIED DEWPOINTS OVER
THE FAR NORTHWEST AND INTO NORTHEAST NORTH DAKOTA. COULD STILL BE
SOME SHOWER/THUNDERSTORM ACTIVITY HERE LATER THIS EVENING AS THE
FRONT MOVES INTO CENTRAL AND EASTERN NORTH DAKOTA. THIS IS COVERED
IN THE CURRENT FORECAST WITH A MENTION OF SHOWERS ACROSS THE FAR
NORTH CENTRAL...AND INTO THE TURTLE MOUNTAINS AREA THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 223 PM CDT SAT AUG 1 2015
SEVERE CONVECTIVE POTENTIAL ACROSS THE JAMES RIVER VALLEY THIS
AFTERNOON HIGHLIGHTS THE SHORT TERM FORECAST.
VISIBLE SATELLITE IMAGERY THROUGH 1920 UTC CONTINUES TO DEPICT A
DEVELOPING CUMULUS FIELD BETWEEN JAMESTOWN...STEELE AND EDGELEY.
THE 13-18 UTC HRRR ITERATIONS HAVE ALL DEPICTED CONVECTIVE
INITIATION FOR THIS AREA BY 21 UTC IN AN ENVIRONMENT CHARACTERIZED
BY ML CAPE AROUND 2000-3000 J/KG AND DEEP LAYER SHEAR OF 30-40
KTS. WITH A SHORTWAVE EVIDENT JUST UPSTREAM ON WATER
VAPOR...CONVECTIVE POTENTIAL IS INCREASING ALONG WITH THE THREAT
FOR LARGE HAIL AND DAMAGING WINDS IN AN ENVIRONMENT SUPPORTIVE OF
SUPERCELLS...AND HAVE THUS ADDED SEVERE WORDING TO THE JAMES RIVER
VALLEY FOR THIS AFTERNOON. EXPECT THE THREAT TO QUICKLY EXIT INTO
THE GRAND FORKS CWA BY 00 UTC.
LATER THIS EVENING A COLD FRONT WILL PROPAGATE FROM NORTHWEST TO
SOUTHEAST ACROSS NORTH DAKOTA...YIELDING A COOLER BUT STILL
SEASONABLE SUNDAY FOR EARLY AUGUST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 240 PM CDT SAT AUG 1 2015
NORTHWEST FLOW ALOFT THROUGH MONDAY NIGHT. DRY CONDITIONS
EXPECTED WITH SURFACE HIGH PRESSURE FIRMLY IN PLACE ACROSS THE
DAKOTAS. DEEP UPPER LOW MOVING SOUTH INTO THE GREAT LAKES REGION
SUNDAY WILL PUSH A BACK DOOR COLD FRONT INTO THE NORTHERN PLAINS
AND KEEP TEMPERATURES RELATIVELY COOL IN THE 70S TO LOW 80S MONDAY
AND TUESDAY.
A MORE ACTIVE PATTERN MATERIALIZES MID TO LATE NEXT WEEK WHEN OUR
FLOW TRANSITIONS TO MORE ZONAL ALLOWING SEVERAL EMBEDDED WAVES TO
MOVE THROUGH THE REGION. BEST THUNDERSTORM CHANCES WILL BE
CONFINED TO THE SOUTH AND WEST INITIALLY...UNTIL LATER IN THE
WEEK WHEN A CLOSED MID LEVEL CROSSES THE ALBERTA ROCKIES AND MOVES
INTO NORTH DAKOTA FRIDAY. TEMPERATURES DO NOT RECOVER MUCH FROM
EARLY IN THE WEEK...AND LOOK TO REMAIN BELOW AVERAGE FOR EARLY
AUGUST WED-FRI (70S TO LOW 80S).
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 543 PM CDT SAT AUG 1 2015
VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD. LIGHT
WINDS SHOULD BECOME SOUTHERLY OR SOUTHWESTERLY AHEAD OF A COLD FRONT
THAT IS FORECAST TO MOVE THROUGH KISN AROUND 00Z...AND THROUGH KMOT
AND KDIK AROUND 04Z SATURDAY EVENING...REACHING KJMS AROUND 09Z.
EXPECT A NORTH TO NORTHWEST FLOW ON SUNDAY AT ALL TAF SITES BEHIND
THE COLD FRONT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...AYD
LONG TERM...NH
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
325 PM CDT SAT AUG 1 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 325 PM CDT SAT AUG 1 2015
TWO SEPARATE SHORTWAVES WILL AFFECT THE REGION THIS
EVENING/OVERNIGHT.
THE FIRST WAVE WILL BRING A SEVERE THREAT TO A PORTION OF SE ND
AND WC MN. CURRENT SFC ANALYSIS INDICATES A WEAK SFC LOW ACROSS
SOUTH-CENTRAL NORTH DAKOTA...WITH A WARM FRONTAL FEATURE
EXTENDING TO THE SOUTHEAST. DEWPOINT VALUES ALONG THESE FEATURES
HAVE POOLED INTO THE MID-UPPER 60S...LEADING TO MLCAPE 3000-3500
J/KG. AS THIS SYSTEM EVOLVES AND PROPAGATES TOWARD THE
FA...ANTICIPATE THUNDERSTORM DEVELOPMENT ACROSS THE FAR SOUTHERN
FA. 0-6KM BULK SHEAR 35-40 KNTS COMBINED WITH THE STRONG
INSTABILITY WILL LEAD TO SEVERE STORMS...ALTHOUGH COVERAGE SHOULD
REMAIN ISOLATED GIVEN CONVECTIVE TEMPS NEAR 90F (SOME CAPPING
ISSUES). THIS ACTIVITY WILL MOVE OUT OF THE REGION BY EARLY
EVENING. DID ADD T+ (SEVERE STORMS POSSIBLE) ACROSS FAR SE ND
WHERE CONFIDENCE IS HIGHER IN THUNDER DEVELOPMENT (LOW LEVEL
CONVERGENCE WILL BE MAXIMIZED...AND THE HRRR HAS CONSISTENTLY
INDICATED DEVELOPMENT FROM RUN TO RUN).
NEXT UP WILL BE THE NORTHERN FA THIS EVENING INTO THE OVERNIGHT
HOURS...AS A STRONGER UPPER WAVE BRINGS A COLD FRONT THROUGH THE
REGION. THIS ACTIVITY WILL ENCOUNTER WEAK INSTABILITY (MUCAPE
500-1000 J/KG) BUT VERY STRONG DEEP LAYER SHEAR (60+
KNOTS)...ALONG WITH MID-LEVEL WINDS IN EXCESS OF 50 KNTS. THE 18Z
HRRR IS INDICATING A SMALL BOW ECHO WITH SFC WIND GUSTS 50-55
KNOTS 02Z-05Z. OF COURSE THAT IS JUST ONE POSSIBLE SOLUTION...BUT
IT DOES SPEAK TO THE POTENTIAL OF WHAT COULD OCCUR ACROSS THE
NORTHERN FA THIS EVENING AND OVERNIGHT. THIS FORCING MAY ALSO
INTERACT WITH INCREASING INSTABILITY FROM THE SOUTH AFTER
MIDNIGHT...WHICH MAY BE ENOUGH FOR A FEW STRONGER STORMS INTO THE
OVERNIGHT HOURS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 325 PM CDT SAT AUG 1 2015
THIS PERIOD STARTS OFF WITH A BROAD UPPER LEVEL LOW OVER ONTARIO
AND COOL HIGH PRESSURE IN PLACE AT THE SURFACE OVER SASKATCHEWAN
AND THE DAKOTAS. THE WEATHER WILL BE DRY AND SLIGHTLY COOLER THAN
AVERAGE FOR THE START OF THE WEEK. HOWEVER...A WEAK UPPER LEVEL
WAVE WILL MOVE EAST IN THE WEAK UPPER FLOW...UNDERCUTTING A
WESTERN U.S. RIDGE BY MID WEEK. THE MODELS HAVE HAD A HARD TIME
WITH THIS SYSTEM. PREVIOUS RUNS HAD MORE INSTABILITY AND MUCH MORE
OF A PRECIPITATION SIGNAL AREA-WIDE. THE LATEST GFS HAS BEST
LIFT/INSTABILITY IN THE FAR SOUTH ON WEDNESDAY NIGHT.
SO...CONFIDENCE IS DECREASING IN WEDNESDAYS SYSTEM. ANOTHER WEAK
WAVE WILL AFFECT PRIMARILY THE SOUTH ON THURSDAY...BUT
AGAIN...THIS ONE HAS TRENDED SOUTHWARD. HOWEVER...FRIDAYS SYSTEM
LOOKS TO BE THE WAVE THAT HAS THE MOST AGREEMENT REGARDING TRACK
AND COULD BRING WIDESPREAD PRECIP TO THE AREA. WITH PLENTY OF
UNCERTAINTY ON THESE WAVES...TOO EARLY TO TALK ABOUT SEVERE
POTENTIAL. PRECIPITATION CHANCES EXIST INTO SATURDAY AS WELL AND
WILL DEPEND ON SPEED OF UPPER LOW. TEMPERATURES LOOK TO BE COOL
FOR MUCH OF THIS PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1248 PM CDT SAT AUG 1 2015
TAFS FOR THE 18Z UPDATE REFLECT MODEST THUNDERSTORM PROBABILITIES
ACROSS NRN RED RIVER VALLEY AND NRN MN LATE TONIGHT.
FIRST...THERE MAY BE SOME THUNDERSTORMS SOUTH AND EAST OF KFAR THIS
AFTERNOON/EVENING AHEAD OF THE COLD FRONT. PROBABILITIES HAVE
INCREASED SLIGHTLY FOR KFAR TO SEE AN AFTERNOON TS CLOSE TO THE
TERMINAL. LAST FEW HRRR MODEL RUNS HAVE HAD TS ACTIVITY NEAR KFAR.
HAVE INCLUDED VCTS AT 23Z FOR NOW.
LATE TONIGHT...A COLD FRONT WILL PUSH THROUGH THE AREA AND MODELS
INDICATE THERE MAY BE SOME THUNDERSTORM ACTIVITY PUSHING
SOUTHEASTWARD AFTER MIDNIGHT. EXPECTING WEAKER THUNDERSTORMS
COMPARED TO THIS AFTERNOONS ACTIVITY NEAR KFAR. HAVE LEFT KDVL
AND KFAR OUT OF THE VCTS MENTION AS THEY WILL BE ON THE SOUTHERN
AND WESTERN EDGE OF THE ACTIVITY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
SHORT TERM...TG
LONG TERM...KNUTSVIG
AVIATION...KNUTSVIG
AREA FORECAST DISCUSSION
NWS BISMARCK ND
243 PM CDT SAT AUG 1 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 223 PM CDT SAT AUG 1 2015
SEVERE CONVECTIVE POTENTIAL ACROSS THE JAMES RIVER VALLEY THIS
AFTERNOON HIGHLIGHTS THE SHORT TERM FORECAST.
VISIBLE SATELLITE IMAGERY THROUGH 1920 UTC CONTINUES TO DEPICT A
DEVELOPING CUMULUS FIELD BETWEEN JAMESTOWN...STEELE AND EDGELEY.
THE 13-18 UTC HRRR ITERATIONS HAVE ALL DEPICTED CONVECTIVE
INITIATION FOR THIS AREA BY 21 UTC IN AN ENVIRONMENT CHARACTERIZED
BY ML CAPE AROUND 2000-3000 J/KG AND DEEP LAYER SHEAR OF 30-40
KTS. WITH A SHORTWAVE EVIDENT JUST UPSTREAM ON WATER
VAPOR...CONVECTIVE POTENTIAL IS INCREASING ALONG WITH THE THREAT
FOR LARGE HAIL AND DAMAGING WINDS IN AN ENVIRONMENT SUPPORTIVE OF
SUPERCELLS...AND HAVE THUS ADDED SEVERE WORDING TO THE JAMES RIVER
VALLEY FOR THIS AFTERNOON. EXPECT THE THREAT TO QUICKLY EXIT INTO
THE GRAND FORKS CWA BY 00 UTC.
LATER THIS EVENING A COLD FRONT WILL PROPAGATE FROM NORTHWEST TO
SOUTHEAST ACROSS NORTH DAKOTA...YIELDING A COOLER BUT STILL
SEASONABLE SUNDAY FOR EARLY AUGUST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 240 PM CDT SAT AUG 1 2015
NORTHWEST FLOW ALOFT THROUGH MONDAY NIGHT. DRY CONDITIONS
EXPECTED WITH SURFACE HIGH PRESSURE FIRMLY IN PLACE ACROSS THE
DAKOTAS. DEEP UPPER LOW MOVING SOUTH INTO THE GREAT LAKES REGION
SUNDAY WILL PUSH A BACK DOOR COLD FRONT INTO THE NORTHERN PLAINS
AND KEEP TEMPERATURES RELATIVELY COOL IN THE 70S TO LOW 80S MONDAY
AND TUESDAY.
A MORE ACTIVE PATTERN MATERIALIZES MID TO LATE NEXT WEEK WHEN OUR
FLOW TRANSITIONS TO MORE ZONAL ALLOWING SEVERAL EMBEDDED WAVES TO
MOVE THROUGH THE REGION. BEST THUNDERSTORM CHANCES WILL BE
CONFINED TO THE SOUTH AND WEST INITIALLY...UNTIL LATER IN THE
WEEK WHEN A CLOSED MID LEVEL CROSSES THE ALBERTA ROCKIES AND MOVES
INTO NORTH DAKOTA FRIDAY. TEMPERATURES DO NOT RECOVER MUCH FROM
EARLY IN THE WEEK...AND LOOK TO REMAIN BELOW AVERAGE FOR EARLY
AUGUST WED-FRI (70S TO LOW 80S).
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 223 PM CDT SAT AUG 1 2015
VFR CONDITIONS WILL CONTINUE THROUGH THE FORECAST PERIOD. LIGHT
WINDS SHOULD BECOME SOUTHERLY OR SOUTHWESTERLY AHEAD OF A COLD FRONT
THAT IS FORECAST TO MOVE THROUGH KISN AROUND 00Z...AND THROUGH KMOT
AND KDIK AROUND 04Z SATURDAY EVENING...REACHING KJMS AROUND 09Z.
SOUTHWEST WINDS COULD BE GUSTY AT TIMES AT KISN AND KDIK THIS
AFTERNOON. ISOLATED THUNDERSTORMS ARE POSSIBLE NEAR AND SOUTH OF
KJMS THIS AFTERNOON...POSSIBLY SEVERE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...AYD
LONG TERM...NH
AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1254 PM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 1249 PM CDT SAT AUG 1 2015
THE MAIN CHALLENGE FOR THE REMAINDER OF THE AFTERNOON IS
CONVECTIVE POTENTIAL ACROSS PRIMARILY THE SOUTHERN JAMES RIVER
VALLEY. THE 12-16 UTC HRRR ITERATIONS CONTINUE TO DEPICT
CONVECTIVE INITIATION FOR THIS AREA BY 21 UTC IN AN ENVIRONMENT
CHARACTERIZED BY ML CAPE AROUND 2000 J/KG AND DEEP LAYER SHEAR OF
25-30 KTS. WITH A SHORTWAVE EVIDENT JUST UPSTREAM ON WATER
VAPOR...CONVECTIVE POTENTIAL IS INCREASING ALONG WITH THE THREAT
FOR LARGE HAIL AND DAMAGING WINDS SHOULD A SUPERCELL DEVELOP.
UPDATE ISSUED AT 926 AM CDT SAT AUG 1 2015
OTHER THAN TO BLEND TO OBSERVED TRENDS THROUGH 14 UTC...THE
ONGOING FORECAST IS ON TRACK WITH A HOT DAY EXPECTED IN THE WARM
SECTOR OF A WEAK SURFACE LOW ACROSS WESTERN NORTH DAKOTA THIS
AFTERNOON. DID MAINTAIN AN ISOLATED TO SCATTERED MENTION OF
THUNDERSTORMS ACROSS THE FAR SOUTHERN JAMES RIVER VALLEY AS
SUPPORTED BY THE 06 AND INCOMING 12 UTC GLOBAL GUIDANCE AND 12-13
UTC HRRR ITERATIONS WHERE LOWER 60S DEWPOINTS ARE EXPECTED TO
REMAIN THIS AFTERNOON.
UPDATE ISSUED AT 616 AM CDT SAT AUG 1 2015
AREA OF CLOUDS WITH A FEW SPRINKLES IN WEAK THETA-E ADVECTION OVER
CENTRAL ND INTO THE JAMES RIVER VALLEY CONTINUE TO SLOWLY SHIFT
TO THE EAST. FOR EARLY MORNING UPDATE WILL ADJUST CLOUD COVER AND
ADD MENTION OF SPRINKLES...ENDING BY MID MORNING.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 301 AM CDT SAT AUG 1 2015
A VERY WARM DAY TODAY HIGHLIGHTS THE SHORT TERM FORECAST.
NORTHWEST UPPER LEVEL JET FLOW CONTINUED OVER THE STATE...WITH
AN UPPER LEVEL LOW OVER HUDSON BAY AND A WARM WESTERN RIDGE OVER THE
WEST COAST AND ROCKIES. WARM AND DRY AIR WAS SOUTHWEST OF THE UPPER
LEVEL JET WITH COOLER AIR TO THE NORTHEAST.
EARLY THIS MORNING ISOLATED SHOWERS DEVELOPED...LIKELY ALONG A
BOUNDARY BETWEEN A SOUTHERLY LOW LEVEL JET ALONG WESTERN NEBRASKA
INTO THE WESTERN DAKOTAS. ENOUGH LIFT WAS OCCURRING IN A NORTHWEST-
TO-SOUTHEAST FASHION ACROSS CENTRAL NORTH DAKOTA. THE LATEST
ITERATION OF THE HRRR INDICATES THE AREA OF ISOLATED SHOWERS
SHIFTING EAST TO THE JAMES VALLEY BEFORE SUNRISE...THEN CONTINUING
EAST OUT OF THE JAMES VALLEY.
A COLD FRONT OVER THE CENTRAL CANADIAN PRAIRIE PROVINCES THIS
MORNING IS FORECAST TO MOVE SOUTH TODAY AND ENTER NORTHWESTERN NORTH
DAKOTA BY THIS EVENING...SWEEPING SOUTHEAST ACROSS THE STATE
TONIGHT. LOOK FOR A VERY WARM DAY TODAY AHEAD OF THE FRONT. WESTERLY
MIXING WINDS ALOFT SHOULD INCREASE WITH THE APPROACH OF THE FRONT
DUE TO THE INCREASING PRESSURE GRADIENT. FORECAST SOUNDINGS INDICATE
AN ADIABATIC LINK FROM THE SURFACE UP TO AROUND H700 THIS AFTERNOON.
WENT ABOVE GUIDANCE FOR MAX TEMPS AND RAISED WINDS A BIT AS WELL
FROM GUIDANCE. LOOKING AT HIGHS TODAY IN THE LOW TO MID 90S OVER
MOST OF WESTERN AND CENTRAL NORTH DAKOTA.
TONIGHT AS THE COLD FRONT SWEEPS SOUTHEAST ACROSS THE STATE...THE
BEST UPPER LEVEL FORCING RESIDES TO OUR NORTHEAST IN THE FLOW OF THE
UPPER JET - WHICH SHOULD HAVE LIFTED NORTHEAST DURING THE DAY
ALLOWING THE VERY WARM AND DRY AIR TO ADVANCE INTO CENTRAL NORTH
DAKOTA. HAVE KEPT THE SLIGHT CHANCES OF THUNDERSTORMS ACROSS THE
TURTLE MOUNTAIN AREA. COOLER AIR MOVES INTO THE STATE TONIGHT WITH
NORTHWEST WINDS BEHIND THE COLD FRONT. KEPT LOWS TONIGHT IN THE 50S
AS THE NORTHWEST WINDS WILL KEEP THE LOWER ATMOSPHERE MIXED ENOUGH
SO THAT TEMPS DO NOT DROP INTO THE 40S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 301 AM CDT SAT AUG 1 2015
COOLER TEMPERATURES EXPECTED OVER THE AREA ON SUNDAY IN THE WAKE
OF THE COLD FRONT. OTHERWISE...DRY CONDITIONS EXPECTED WITH UPPER
RIDGE AXIS SLIDING OVER THE ROCKIES AND SURFACE HIGH SETTLING OVER
THE REGION. DRY WEATHER CONTINUES INTO MONDAY WITH RIDGE AXIS
PUSHING TOWARDS THE NORTHERN PLAINS.
ACTIVE WEATHER PATTERN EXPECTED TOWARDS MID-WEEK WITH RIDGE
BREAKING DOWN AND A VARIETY OF SHORT WAVES EJECTING OVER THE AREA
FROM A BROAD UPPER LOW OVER BRITISH COLUMBIA. UNSETTLED PATTERN
CONTINUES INTO THE END OF THE WEEK AS LOW STARTS TO MAKE ITS WAY
EASTERLY. BELOW AVERAGE TEMPERATURES EXPECTED THROUGH THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1249 PM CDT SAT AUG 1 2015
VFR CONDITIONS WILL CONTINUE THROUGH THE FORECAST PERIOD. LIGHT
WINDS SHOULD BECOME SOUTHERLY OR SOUTHWESTERLY AHEAD OF A COLD FRONT
THAT IS FORECAST TO MOVE THROUGH KISN AROUND 00Z...AND THROUGH KMOT
AND KDIK AROUND 04Z SATURDAY EVENING...REACHING KJMS AROUND 09Z.
SOUTHWEST WINDS COULD BE GUSTY AT TIMES AT KISN AND KDIK THIS
AFTERNOON. ISOLATED THUNDERSTORMS ARE POSSIBLE SOUTH OF KJMS THIS
AFTERNOON.
&&
.FIRE WEATHER...
ISSUED AT 301 AM CDT SAT AUG 1 2015
AN ADIABATIC LAPSE RATE UP TO H700 THIS AFTERNOON WILL ALLOW
MIXING WINDS ALOFT TO LINK WITH THE SURFACE. EXPECTING 15 TO 20
MPH WINDS FOR A TIME THIS AFTERNOON IN THE WEST AS TEMPERATURES
REACH INTO THE 90S. DEWPOINTS IN THE 40S OVER SOUTHWESTERN NORTH
DAKOTA THIS MORNING ARE EXPECTED TO DROP INTO THE 30S THIS
AFTERNOON AS THE LOWER ATMOSPHERE MIXES WITH MID LEVELS.
TEMPERATURES IN THE MID 90S WITH DEWPOINTS IN THE 30S SHOULD
RESULT IN MINIMUM RELATIVE HUMIDITY VALUES IN THE 10 TO 15 PERCENT
RANGE OVER MUCH OF WESTERN NORTH DAKOTA...MAINLY ALONG AND WEST OF
A LINE FROM WILLISTON TO WATFORD CITY TO DICKINSON AND HETTINGER.
IN ADDITION...WINDS ALOFT SHOULD ALSO MIX DOWN TO THE SURFACE FOR
A TIME THIS AFTERNOON...WITH WESTERLY WINDS OF 15 TO 20 MPH
EXPECTED.
EXPECT THAT GRASSLANDS IN THE SOUTHWEST ARE CURING QUICKLY.
THE LATEST ASSESSMENT FROM LAND MANAGERS INDICATED THAT SLOPE AND
BOWMAN COUNTIES WOULD LIKELY BE THE FIRST TO REACH CRITICAL FUEL
MOISTURE LEVELS AT SOME POINT. WEATHER CONDITIONS EXPECTED TODAY
WOULD WARRANT A RED FLAG MENTION FOR WILLISTON TO HETTINGER AND
WESTWARD...BUT UNDERSTAND THAT GRASSLANDS HAVE NOT YET REACHED
CRITICAL FUEL MOISTURE LEVELS.
COOLER CONDITIONS WITH HIGHER RELATIVE HUMIDITY VALUES ARE EXPECTED
ON SUNDAY...AFTER A COLD FRONTAL PASSAGE SATURDAY NIGHT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AYD
SHORT TERM...JV
LONG TERM...JJS
AVIATION...AYD
FIRE WEATHER...JV
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1248 PM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 1248 PM CDT SAT AUG 1 2015
SPC DID EXTEND THE MARGINAL SEVERE RISK INTO SOUTHEAST NORTH
DAKOTA...WHICH SEEMS APPROPRIATE. AT 17Z...DEWPOINT VALUES AHEAD
OF A WEAK SFC LOW/CONVERGENCE AREA ARE POOLING INTO THE MID-UPPER
60S...WHICH HAD LED TO MLCAPE 2000-2500 J/KG ACROSS SOUTH CENTRAL
NORTH DAKOTA...WHICH WILL SLOWLY PROPAGATE EASTWARD. THE CAP IS
STILL STRONG...BUT AS TEMPERATURES APPROACH 90F THIS CAP WILL
ERODE. CURRENT THINKING IS THAT THERE WILL BE A BRIEF WINDOW OF
OPPORTUNITY FOR STORM DEVELOPMENT ACROSS THE SOUTHERN FA DURING
THE LATE AFTERNOON HOURS. STORMS SHOULD QUICKLY DIMINISH THIS
EVENING CONSIDERING CONVECTIVE TEMPS NEAR 90F. ANY ISOLD STORM
THAT DOES DEVELOP WILL HAVE THE POTENTIAL TO BE SEVERE GIVEN 0-6KM
SHEAR 35-40 KNTS ALONG WITH THE MODERATE INSTABILITY.
AN AREA OF STORMS WILL AFFECT THE NORTHERN FA WITH THE PASSAGE OF
ANOTHER UPPER LEVEL WAVE TONIGHT. ALTHOUGH DEEP LAYER SHEAR WILL
BE VERY STRONG (60+ KNOTS)...INSTABILITY SHOULD BE VERY WEAK. A
STRONGER WIND GUST MAY BE POSSIBLE GIVEN 500MB WINDS AOA 50
KNOTS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 356 AM CDT SAT AUG 1 2015
NORTHWEST-SOUTHEAST ORIENTATED UPPER LEVEL JET ESSENTIALLY REMAINS
OVER THE NORTHEAST ZONES HOWEVER JET DOES OSCILLATE NORTHEAST OF THE
FORECAST AREA THEN BACK OVER THE NORTHEAST ZONES AS SHORT WAVES MOVE
THROUGH THE FLOW. UPPER LEVEL TROUGH OVER NORTHERN MAN WILL ROTATE
ACROSS ONTARIO SAT NIGHT ELSEWHERE WATER VAPOR LOOP INDICATED SHORT
WAVES OVER CENTRAL SASK AND ANOTHER OVER ALTA/BC BORDER. BC SHORT
WAVE WILL DROP SOUTH ACROSS THE GREAT LAKE STATES SUN AND AMPLIFY
THE UPPER TROUGH EAST OF THE AREA. RIDGE BUILDING COMMENCES IN THE
WESTERN US SUN AND SHIFTS INTO THE HIGH PLAINS BY 84 HOURS.
PRECIPITABLE WATER INCREASES OVER AN INCH IN THE SOUTH WITH SURFACE
TROUGH MOVING THROUGH. SHOWALTERS BECOME NEGATIVE OVER THE SOUTHERN
ZONES THIS AFTERNOON AND EVENING WITH LOW LEVEL MOISTURE. SHOWALTERS
ALSO BECOME NEGATIVE IN THE NORTH THIS AFTERNOON AND OVERNIGHT WITH
APPROACHING SHORT WAVE. PRECIPITABLE WATER ALSO INCREASES OVER AN
INCH FROM THE NORTH WITH TROUGH MOVING ACROSS SOUTHERN CANADA.
WEAK SURFACE LOW OVER THE WESTERN DAKOTAS WILL MOVE INTO MN AND
DISSIPATE THIS EVENING. ANOTHER SURFACE LOW OVER SOUTHERN ALTA WILL
MOVE INTO MN BY 12Z SUN. THEN HIGH PRESSURE FOLLOWS FOR THE REST OF
THE PERIOD.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 356 AM CDT SAT AUG 1 2015
FOR TUESDAY THROUGH FRIDAY...LONG RANGE GFS/ECMWF HAVE REMAINED IN
FAIR AGREEMENT IN SHOWING UPPER TROUGH OVER ONTARIO MOVING EAST AND
A WESTERLY FLOW AT 500 MB SETTING UP OVER THE NRN PLAINS/SRN CANADA
MID TO LATE WEEK. WITH THIS WILL COME A COUPLE OF DISTURBANCES WITH
THUNDERSTORM CHANCES. 00Z ECMWF HAS A TAD WETTER PATTERN VS A BIT
DRIER 00Z GFS. BLENDED MODEL SOLN HAVE POPS IN THE AREA WED-FRI AND
LEFT THEM FOR NOW. THE MAIN UPPER HEAT RIDGE WILL REMAIN OVER THE
SRN PLAINS AND AREA WILL BE A TAD BELOW NORMAL TEMP REGIME THRU THE
PD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1248 PM CDT SAT AUG 1 2015
TAFS FOR THE 18Z UPDATE REFLECT MODEST THUNDERSTORM PROBABILITIES
ACROSS NRN RED RIVER VALLEY AND NRN MN LATE TONIGHT.
FIRST...THERE MAY BE SOME THUNDERSTORMS SOUTH AND EAST OF KFAR THIS
AFTERNOON/EVENING AHEAD OF THE COLD FRONT. PROBABILITIES HAVE
INCREASED SLIGHTLY FOR KFAR TO SEE AN AFTERNOON TS CLOSE TO THE
TERMINAL. LAST FEW HRRR MODEL RUNS HAVE HAD TS ACTIVITY NEAR KFAR.
HAVE INCLUDED VCTS AT 23Z FOR NOW.
LATE TONIGHT...A COLD FRONT WILL PUSH THROUGH THE AREA AND MODELS
INDICATE THERE MAY BE SOME THUNDERSTORM ACTIVITY PUSHING
SOUTHEASTWARD AFTER MIDNIGHT. EXPECTING WEAKER THUNDERSTORMS
COMPARED TO THIS AFTERNOONS ACTIVITY NEAR KFAR. HAVE LEFT KDVL
AND KFAR OUT OF THE VCTS MENTION AS THEY WILL BE ON THE SOUTHERN
AND WESTERN EDGE OF THE ACTIVITY.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...TG
SHORT TERM...HOPPES
LONG TERM...RIDDLE
AVIATION...KNUTSVIG
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1216 PM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 1027 AM CDT SAT AUG 1 2015
INITIAL SHORTWAVE ENERGY SLIGHTLY STRONGER THAN MODEL GUIDANCE
ANTICIPATED OVERNIGHT...WITH LLJ CONTINUING TO DEVELOP SCATTERED
STORMS ALONG AN ELEVATED BOUNDARY OVER SOUTH CENTRAL SD AND INTO
NEBRASKA. SHORT TERM GUIDANCE CONTINUES TO INDICATE THAT AS THE
LEAD WAVE MOVES SOUTHEAST...THE LLJ WILL GRADUALLY BACK WESTWARD
BY EARLY AFTERNOON AND SHOULD TAPER OFF THIS CONVECTION. 12Z
NAM/GFS PERFORMING VERY POORLY WITH THIS CONVECTION.
SECONDARY SHORTWAVE NOW ENTERING WESTERN ND ARRIVING SLIGHTLY
SLOWER THAN ANTICIPATED...BUT ALREADY DEVELOPING A SFC LOW WEST
OF BISMARCK. A SFC WARM FRONT STRETCHES SOUTHEAST OF THIS
LOW...OVER NORTHEASTER SD AND INTO SW MN.
BIGGEST QUESTIONS FOR THE AFTERNOON HINGE ON THIS LINGERING CLOUD
COVER...AND GRADUAL MIXDOWN OF SLIGHTLY DRIER AIR ALOFT. NAM
AGAIN VERY UNRELIABLE WITH BOUNDARY LAYER MOISTURE AT 12Z...BUT
FEEL HRRR...EXP-HRRR AND RAP FAR TOO AGGRESSIVE WITH THE MIXDOWN.
NEVERTHELESS...FOCUS FOR CONVECTION MAY SHIFT SLIGHTLY THIS
AFTERNOON...ALONG ADVANCING WARM FRONT OVER MN AND NE SD...AND
ALONG DIFFERENTIAL HEATING AXIS ACROSS OUR SWRN COUNTIES. THE
TIMING OF THIS SECONDARY WAVE IS ALSO NOT AS FAVORABLE.
FOR NOW...HAVE ADJUSTED POPS SLIGHTLY...AND LOWERED TEMPERATURES A
HAIR IN THE FAR SOUTH AND SOUTHWEST. THERE STILL APPEARS TO BE
POTENTIAL FOR A FEW CLUSTERS OF STRONG STORMS LATER TODAY...BUT
AGAIN MESOSCALE DETAILS STILL NOT RESOLVED MAY DRIVE THIS
OPPORTUNITY.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CDT SAT AUG 1 2015
A SHORT WAVE PRESENTLY LOCATED OVER EASTERN MONTANA EARLY THIS
MORNING WILL CONTINUE TO SLIDE SOUTHWARD TODAY ON A NORTHWESTERLY
UPPER LEVEL FLOW...AND WILL PLAY A PART IN OUR WEATHER FOR LATER
THIS AFTERNOON. CURRENT RADAR SHOWING A LINE OF SHOWERS AND
THUNDERSTORMS DEVELOPING THROUGH SOUTH CENTRAL SD INTO NORTH CENTRAL
NE ALONG AN INSTABILITY AXIS AS MIDLEVEL THETA E ADVECTION SPREADS
INTO THAT AREA OUT AHEAD OF THE AFOREMENTIONED WAVE. MAY SEE THESE
STORMS CONTINUE OVER THAT AREA THROUGH THE MID MORNING BEFORE THE
LOW LEVEL JET WEAKENS. AFTER THAT WILL MOST LIKELY SEE CONVECTIVE
ACTIVITY WANE INTO THE AFTERNOON AS A CAP STRENGTHENS ACROSS THE
AREA. BY AFTERNOON THE SHORTWAVE BEGINS TO EXERT INFLUENCE ON THE
REGION WITH COOLING TEMPERATURES ALOFT WEAKENING THE CAP. STILL
SEEING SOME MODEL DIFFERENCES WITH REGARD TO LOWER LEVEL MOISTURE
AND RESULTANT DIFFERENCES IN THE AMOUNT OF INSTABILITY DURING THE
AFTERNOON...THOUGH EITHER WAY THERE SHOULD BE SUFFICIENT CAPE AS
TEMPERATURES WARM INTO THE UPPER 80S TO LOWER 90S TO SUPPORT
VIGOROUS UPDRAFTS IN STORMS WHICH ARE EXPECTED TO DEVELOP BY LATE
AFTERNOON THROUGH THE LOWER MISSOURI RIVER VALLEY. THIS CONVECTIVE
ACTIVITY WILL THEN BECOME MORE FOCUSED IN NORTHWESTERN IOWA AND
PORTIONS OF SOUTHWESTERN MINNESOTA BY LATE AFTERNOON AND EVENING AS
A LOW LEVEL JET STRENGTHENS OVER THAT AREA. EFFECTIVE SHEAR VALUES
LOOK TO BE RUNNING IN EXCESS OF 40 KTS...SO SEVERE STORMS WILL BE A
POSSIBILITY WITH LARGE HAIL AND DAMAGING WINDS. THINKING THAT CANNOT
COMPLETELY RULE OUT AN ISOLATED TORNADO WITH INITIAL CONVECTIVE
DEVELOPMENT THROUGH THE LOWER MISSOURI RIVER VALLEY...WITH LOW LCL
HEIGHTS AND FAIRLY STRONG 0 TO 1 KM SHEAR.
WILL SEE ANY STORMS EVOLVE EASTWARD THROUGH THE EVENING AND EARLY
NIGHT TIME HOURS AS THE SHORTWAVE SLIDES INTO CENTRAL AND EASTERN
IOWA BY EARLY SUNDAY MORNING. SOUTHWESTERLY WINDS WILL NOT BE QUITE
AS LIGHT TONIGHT...AND IT WILL BE A MILD NIGHT WITH LOWS GENERALLY
MID TO UPPER 60S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 340 AM CDT SAT AUG 1 2015
ON SUNDAY...THE COOL FRONT WILL MOVE ACROSS THE AREA...EXITING
NORTHWEST IOWA BY EARLY AFTERNOON. THIS WILL SHIFT WINDS TO THE
NORTHWEST AT 10 TO 20 MPH WITH GUSTS UP TO 30 MPH IN SW MN DURING
THE AFTERNOON. THIS WILL RESULT IN A WELL MIXED ATMOSPHERE.
DESPITE SOMEWHAT COOLER AIR ADVECTING IN AT LOW LEVEL...
TEMPERATURES ARE EXPECTED TO STILL WARM INTO THE MID 80S TO LOWER
90S DUE TO MIXING. THIS WILL ALSO MIX DOWN DRIER AIR WITH
AFTERNOON DEW POINTS IN THE LOWER 50S OVER MUCH OF SE SOUTH DAKOTA
AND SW MN DURING THE AFTERNOON. A LITTLE MORE MOISTURE CAN BE
EXPECTED IN NW IOWA. WINDS ARE EXPECTED TO DROP OFF QUICKLY ON
SUNDAY EVENING AND WITH FAIRLY DRY AIR IN PLACE MOST PLACES NORTH
OF I90 WILL SEE LOWS IN THE UPPER 50S WITH LOWER 60S SOUTH OF I90.
MODEL DIFFERENCES INCREASE ON MONDAY. THE NAM SHOWS A WEAK UPPER
LEVEL WAVE MOVING IN THE NORTHWEST FLOW. AS THIS WAVE MOVES INTO
THE SD...THE 850 MB BOUNDARY IS DRAWN NORTHWARD INTO FAR SOUTHERN
SOUTH DAKOTA AND NORTHERN IOWA. THE GFS AND 00Z ECMWF DO NOT
REALLY SHOW THIS WAVE AND INSTEAD HAVE A WEAK WAVE MOVE EAST OUT
OF COLORADO INTO THE HIGH PLAINS. AS A RESULT THE 850 MB BOUNDARY
REMAINS BETWEEN I80 AND HWY 20. HAVE GENERALLY SIDED WITH THIS
SOLUTION. AS A RESULT ON MONDAY...WHILE SKIES WILL BECOME PARTLY
CLOUDY NEAR THE MISSOURI RIVER AND INTO NW IA...IT WILL AGAIN BE
MOSTLY SUNNY ALONG AND NORTH OF I90. THERE WILL AGAIN BE DEEP
NORTHERLY FLOW IN THIS AREA AND THIS WILL RESULT IN A WELL MIXED
ATMOSPHERE. AFTERNOON DEW POINTS WILL FALL INTO THE LOWER 50S WITH
TEMPERATURES WARMING INTO THE LOW TO MID 80S. FARTHER SOUTH...WITH
A FEW MORE CLOUDS AND LESS MIXING...DEW POINTS WILL REMAIN IN THE
LOWER 60S WITH HIGHS GENERALLY IN THE MID 80S.
WITH SOME CONVERGENCE IN THE VICINITY OF THE BOUNDARY IN NRN
NEBRASKA AND LI/S AROUND -2...COULD SEE A FEW SHOWERS OR
THUNDERSTORMS DEVELOP NEAR THE MISSOURI RIVER LATE MONDAY MORNING
INTO MONDAY AFTERNOON. THE BEST CHANCE FOR PRECIPITATION WILL BE
MONDAY EVENING AS THE UPPER WAVE APPROACHES THE AREA. WHILE IT
APPEARS THE BEST CHANCE FOR PRECIPITATION WILL BE SOUTH OF HIGHWAY
20...GIVEN UNCERTAINTY IN THE LOCATION OF THE 850 MB FRONT...HAVE
SLIGHT CHANCE POPS AS FAR NORTH AS I90 ON MONDAY EVENING WITH 30
TO 40 PERCENT POPS AROUND SIOUX CITY AND STORM LAKE. WITH THE
BETTER CONVERGENCE SHIFTING TO THE SOUTH THROUGH THE NIGHT...THE
PRECIPITATION CHANCE SHOULD DECREASE AFTER MIDNIGHT.
FOR THE EXTENDED...TUESDAY THROUGH FRIDAY...THERE ARE NOT MAJOR
DIFFERENCES BETWEEN MODEL SOLUTIONS. THE GFS...ECMWF...GEFS AND
CANADIAN ALL SHOW AN UPPER LOW NEAR HUDSON BAY AND A RIDGE OVER THE
WESTERN US. THIS RIDGE GRADUALLY MOVES EAST THROUGH THE WEEK
ALTHOUGH A WEAK WAVE MOVING OVER THE RIDGE MID TO LATE WEEK WILL
PREVENT ANY WARMING ACROSS THE AREA. AND IT IS THIS WAVE THAT WILL
DEFINE ANY PRECIPITATION CHANCES. TUESDAY LOOKS PRIMARILY DRY
EXCEPT FOR THE POSSIBILITY OF THUNDERSTORMS IN THE MISSOURI
VALLEY IN THE LATE AFTERNOON AND EVENING WHERE THERE IS MORE
INSTABILITY. WITH LITTLE IF ANY RAINFALL...HIGHS WILL GENERALLY BE
IN THE LOWER 80S. WEDNESDAY WILL MOST LIKELY BE DRY AS WELL
ALTHOUGH THE FASTER ECMWF DOES BRING THE WAVE EAST BY LATE
WEDNESDAY AFTERNOON. FOR THIS REASON HAVE A SLIGHT CHANCE OF
THUNDERSTORMS ON WEDNESDAY. ALL MODELS BRING THIS WAVE THROUGH
LATER WEDNESDAY NIGHT AND THURSDAY WHEN THE BEST CHANCE FOR
THUNDERSTORMS EXIST. THUNDERSTORMS CHANCES DECREASE THURSDAY NIGHT
AND FRIDAY. WITH MORE CLOUDS AND THE CHANCE OF RAIN...HIGHS
WEDNESDAY THROUGH FRIDAY WILL GENERALLY BE IN THE UPPER 70S TO
LOWER 80S. LOWS WILL BE FROM THE UPPER 50S TO LOWER 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1214 PM CDT SAT AUG 1 2015
INFLUENCE FROM CONVECTION OVER NEBRASKA CONTINUES TO INFLUENCE THE
WEATHER FOR THE REMAINDER OF THE AFTERNOON/EVENING. THERE STILL
REMAINS A CHANCE FOR CONVECTION LATER TODAY...BUT PROBABILITIES
TOO LOW TO INCLUDE IN TAFS ATTM. VFR CONDITIONS WILL PERSIST INTO
THE OVERNIGHT HOURS...WITH A FEW WIDELY SCATTERED STORMS LATE THIS
EVENING POSSIBLE.
OTHERWISE...WILL WATCH A FRONT MOVE THROUGH MID-MORNING
SUNDAY...BRINGING GUSTY NORTHWEST WINDS.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...DUX
SHORT TERM...JM
LONG TERM...SCHUMACHER
AVIATION...DUX
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
304 PM CDT SAT AUG 1 2015
.SHORT TERM /NOW THROUGH SUNDAY NIGHT/...SATELLITE IMAGES THIS
AFTERNOON INDICATE MOSTLY MID TO HIGH CLOUDS NEAR THE COAST WITH A
SCATTERED CU FIELD ACROSS THE WESTERN PORTIONS OF THE DEEP SOUTH
TEXAS. THE LATEST BRO RADAR CONTINUES TO SHOW SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS OVER THE GULF OF MEXICO WATERS...20 TO
60 NAUTICAL MILES EAST OF PADRE ISLAND. THE WEAK 500MB
LOW/INVERTED TROUGH ACROSS THE WESTERN GULF OF MEXICO THIS
AFTERNOON WILL CONTINUE TO PROVIDE LOW TO MID LEVEL MOISTURE OVER
THE WESTERN GULF OF MEXICO AND ALONG THE LOWER TEXAS COAST. THE
12Z BRO SOUNDING SHOWS PRECIPITABLE WATERS OF 1.97 INCHES. THIS
WILL SUPPORT A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS
THE COASTAL SECTIONS OF DEEP SOUTH TEXAS FOR THE REST OF THIS
AFTERNOON WITH DRIER AIR FARTHER INLAND. THE LATEST HRRR KEEPS
MOST...IF NOT ALL...OF THE CONVECTION OFFSHORE AND SOUTH OF THE
RIO GRANDE RIVER NOW THROUGH THIS EVENING. CONVECTION IS EXPECTED
TO DECREASE IN COVERAGE THIS EVENING BEFORE REDEVELOPING OVER THE
GULF WATERS AFTER MIDNIGHT. THE WEAK MID TO UPPER LEVEL FEATURE IS
EXPECTED TO MOVE WESTWARD ACROSS NORTHEAST MEXICO TONIGHT INTO
SUNDAY. LINGERING MOISTURE COMBINED WITH DAYTIME HEATING WILL
PROVIDE A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE
LOWER PORTIONS OF THE RIO GRANDE VALLEY ON SUNDAY.
.LONG TERM /MONDAY THROUGH SATURDAY/...THE MAIN ISSUE IN THE
LONGER RANGE PERIOD WILL BE THE HEAT POTENTIAL ACROSS THE RGV. THE
GFS AND ECMWF BOTH RESTRENGTHEN THE 500 MB RIDGING IN PLACE OVER
THE SOUTH CENTRAL PLAINS STATES NEXT WEEK. THIS WILL RESULT IN A
DRIER AND MORE STABLE AIRMASS OVER DEEP SOUTH TX ONCE AGAIN
YIELDING ABOVE NORMAL TEMPS THROUGH DAY 7. THE DEEPER LAYER
MOISTURE VALUES REMAIN PRETTY LIMITED ACROSS THE AREA THROUGH THE
EXTENDED RANGE PERIOD. ONLY A VERY SHALLOW MOISTURE LAYER MAY
PERSIST ON THROUGH DAY 7 WHICH WILL ALLOW FOR SOME LOW LEVEL CLD
COVER TO PERSIST ON THROUGH THE PERIOD. OTHERWISE EXPECT NEAR
ZERO RAIN CHANCES TO PREVAIL.
THE GFS MEX AND ECMWF MODEL HIGH/LOW TEMPS THROUGH THE PERIOD ARE
IN PRETTY DECENT AGREEMENT. SO WILL GO WITH A GENERAL 50/50 BLEND
OF THE TWO MODEL SETS FOR TEMPS. THE GFS MEX POPS STILL TRY TO
TREND TOWARDS SOME SLGT CHC POPS LATE IN THE PERIOD. I BELIEVE
THAT THIS IS MODEL TREND IS BEING SKEWED HIGH DUE TO CLIMO
INFLUENCES. SO WILL GO CLOSER TO THE ECMWF POPS IN THE LONG TERM.
&&
.MARINE...NOW THROUGH SUNDAY NIGHT...BUOY020 IS CURRENTLY REPORTING
SEAS OF 1 FOOT WITH NORTH WINDS NEAR 4 KNOTS. LIGHT AND VARIABLE
WINDS WILL PREVAIL ACROSS THE LOWER TEXAS COASTAL WATERS NOW THROUGH
SUNDAY NIGHT DUE TO A WEAK PRESSURE GRADIENT ACROSS THE WESTERN
GULF. WINDS AND SEAS WILL BE HIGHER IN AND NEAR THUNDERSTORMS
ASSOCIATED WITH THE WEAK MID TO UPPER LEVEL DISTURBANCE OVER THE
WESTERN GULF.
MONDAY THROUGH THURSDAY...THE PGF WILL START OF NEXT WEEK FAIRLY
WEAK ALLOWING FOR FAIRLY LOW WINDS AND SEAS TO PREVAIL. THE PGF
WILL THEN START TO STRENGTHEN SOMEWHAT STARTING LATE TUES/WED AS A
SURFACE LOW DEVELOPS OVER THE SOUTHERN PLAINS STATES. THIS MAY
PUSH THE WINDS AND SEAS UP LATE IN THE MARINE FORECAST PERIOD TO
POSSIBLY PRODUCE SOME SCEC CONDITIONS WED/THURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 77 92 79 94 / 10 20 10 10
BROWNSVILLE 76 94 78 95 / 10 20 10 10
HARLINGEN 75 95 77 98 / 10 40 10 10
MCALLEN 76 99 79 102 / 10 30 10 10
RIO GRANDE CITY 75 101 78 104 / 10 20 10 10
SOUTH PADRE ISLAND 78 88 80 90 / 10 20 10 10
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
SHORT TERM...63
LONG TERM...60
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1241 PM EDT SAT AUG 1 2015
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN THE AREA INTO SUNDAY EVENING. AN
UPPER DISTURBANCE PASSES ACROSS THE GREAT LAKES MONDAY. A COLD
FRONT WILL DROP SOUTH INTO THE AREA ON TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 950 AM EDT SATURDAY...
STILL MAINLY A TEMPERATURE FORECAST THIS AFTERNOON UNDER WEAK HIGH
PRESSURE AND WEST/NW FLOW ALOFT. WEAK FRONT/TROUGH APPROACHING
FROM THE NW MAY GENERATE A BIT OF CU NW AS SUPPORTED BY THE NAM CU
RULE BUT EXPECTING MUCH OF THIS TO MIX OUT UNDER SUCH DRY AIR
ALOFT OFF MORNING RAOBS. LATEST NAM AND HRRR ALSO GENERATING A FEW
-SHRA FAR NORTH BUT LOOKS OVERDONE GIVEN SO MUCH DRY AIR DESPITE
SOME DEWPOINT RISES SO LEAVING OUT MENTION THIS AFTERNOON. OTRW
EXPECTING ANOTHER WARM AND DRY AFTERNOON WITH A LARGE DIURNAL
SWING IN TEMPS GIVEN HEATING OF DRY AIR AND WEAK DOWNSLOPING OUT
EAST. MORNING THICKNESS AND LATEST MOS DOES SUPPORT A LITTLE BUMP
IN HIGHS SO RAISED A DEGREE OR TWO IN SPOTS ESPCLY EAST WHERE A
FEW LOW 90S APPEAR LIKELY.
PREVIOUS DISCUSSION AS OF 222 AM EDT SATURDAY...
WEAK UPPER WAVE OVER THE OHIO VALLEY WILL SLIDE SOUTHEAST AND ERODE
OVER THE PIEDMONT THIS AFTERNOON. AIRMASS REMAINS DRY SO NOT
EXPECTING ANYTHING BUT A FEW CU/SC. THIS REINFORCES THE DRIER AIR.
WITH PLENTY OF SUNSHINE WILL BE WARM/SEASONAL...HIGHS RANGING FROM
THE UPPER 70S TO LOWER 80S MOUNTAINS...TO AROUND 90 EAST OF THE BLUE
RIDGE...AND IN THE ROANOKE VALLEY NORTH TOWARD LEXINGTON.
TONIGHT...SKIES STAY CLEAR WITH HIGH PRESSURE BUILDING OVERHEAD.
COOP MOS TAKING TEMPS DOWN INTO THE UPPER 40S AT PLACES LIKE BURKES
GARDEN AND JEFFERSON. NO THAT AGGRESSIVE WITH THE COOLER AIR BUT
THINK A FEW HIGHER VALLEYS COULD REACH 50. MOST OF THE MOUNTAINS
WILL DROP INTO THE 50S..WITH LOWER TO MID 60S EAST.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
AS OF 250 AM EDT SATURDAY...
UPPER LEVEL TROUGHING WILL HOLD IN PLACE THROUGH THE FIRST DAYS OF
NEXT WEEK AS THE CENTER OF THE TROUGH MEANDERS AROUND THE HUDSON BAY
REGION...KEEPING THE MID ATLANTIC SITUATED IN WESTERLY UPPER LEVEL
WINDFLOW.
HIGH PRESSURE IN THE LOW LEVELS WILL REMAIN SITUATED ACROSS THE
CENTRAL APPALACHIANS ON SUNDAY...MAINTAINING DRY CONDITIONS UNDER
MOSTLY CLEAR SKIES WITH A LIGHT NORTHWEST WIND.
AN UPPER LEVEL DISTURBANCE WILL PASS ACROSS THE GREAT LAKES ON
MONDAY...POTENTIALLY BRINGING A FEW SHOWERS TO THE WESTERN RIDGES
DURING THE AFTERNOON/EVENING. DOES NOT APPEAR TO BE ENOUGH SUPPORT
FOR THIS ACTIVITY TO SURVIVE CROSSING THE CONTINENTAL DIVIDE
HOWEVER...AS DOWNSLOPE WINDS CAUSE ANY TO DISSIPATE.
A COLD FRONT WILL DROP SOUTH ON TUESDAY...PROMOTING GREATER
INSTABILITY AS WINDS SHIFT SOUTHWESTERLY ACROSS OUR AREA. AS THE
FRONT STALLS NORTH OF OUR AREA TUESDAY NIGHT...WILL MAINTAIN LOW
RAIN CHANCES IN THE FORECAST AS WEAK IMPULSES RIDE ALONG THE FRONT
INTO THE MID ATLANTIC FROM THE WEST.
EXPECT A WARMING TREND THROUGH THE PERIOD AS TROUGHING ALOFT BECOMES
LESS PRONOUNCED BY MID WEEK. EXPECT HIGHS IN THE LOW/MID 80S FOR THE
MOUNTAINS SUNDAY...REACHING INTO THE UPPER 80S/LOW 90S FOR THE
PIEDMONT. AFTERNOON HIGHS WILL WARM 1-2 DEGREES EACH DAY THEREAFTER.
TEMPERATURES STILL SLIGHTLY BELOW NORMAL FOR SUNDAY NIGHT AS HIGH
PRESSURE PROMOTES STRONG RADIATIONAL COOLING...HOWEVER OVERNIGHT
TEMPERATURES WILL MODERATE TOWARD MID WEEK TO MID/UPPER 60S
AREAWIDE AS CLOUD COVER AND SOUTHWESTERLY WINDFLOW RETURNS.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 250 AM EDT SATURDAY...
EAST-WEST BAROCLINIC ZONE WILL THEN BECOME ESTABLISHED OVER THE
FORECAST AREA FOR THE LONG-TERM PERIOD...WITH UPSTREAM SHORT WAVES
AND/OR MESOSCALE VORTICITY CENTERS FROM DECAYING OLD MIDWEST
CONVECTIVE COMPLEXES PROVIDING SUFFICIENT ENERGY/SUPPORT TO MAINTAIN
THREAT FOR SCATTERED CONVECTION THROUGH THE PERIOD.
GRADUALLY RISING DEW POINTS WILL SLOWLY COMPRESS THE DIURNAL
TEMPERATURE CURVE BACK TO AROUND 20F AS SULTRY AIRMASS SLOWLY
REESTABLISHES ITSELF OVER THE AREA. EXPECT OVERNIGHT LOWS DURING THE
PERIOD TO RANGE FROM THE 60S IN THE MOUNTAINS TO AROUND 70 IN THE
PIEDMONT...WITH HIGHS RANGING FROM MAINLY 80S IN THE MOUNTAINS TO
LOWER-MID 90S ACROSS THE PIEDMONT.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
AS OF 1230 PM EDT SATURDAY...
EXPECTING CU FIELD ACROSS THE NW TO GRADUALLY EXPAND SOUTHEAST
THIS AFTERNOON AHEAD OF A WEAK SURFACE TROUGH THAT WILL CROSS THE
REGION BY THIS EVENING. THIS MAY RESULT IN AREAS OF BKN 4-6K FT
CIGS AT TIMES FROM KLWB TO KBLF/KBCB BUT NOT EXPECTING MUCH IN THE
WAY OF SHOWERS GIVEN LOW LEVEL DRYNESS. SHOULD SEE THIS CLOUDINESS
FADE WITH LOSS OF HEATING EXCEPT PERHAPS ACROSS THE FAR WESTERN
RIDGES WHERE UPSLOPE WILL KICK IN AND POSSIBLY KEEP SOME SCATTERED
STRATO-CU LINGERING THIS EVENING. OTRW VFR CONDITIONS ARE
EXPECTED TO PREVAIL THIS AFTERNOON THROUGH SUNDAY. THE ONLY OTHER
EXCEPTION WILL BE SOME BRIEF...EARLY MORNING PATCHY RIVER OR
MOUNTAIN VALLEY FOG AT KLWB BUT IFFY AS TO HOW LOW VSBYS WILL GO
GIVEN LIKELY PATCHY/ISOLATED NATURE TO THE FOG. THUS KEPT TREND
TOWARD A PERIOD OF MVFR AT KLWB BUT LITTLE ELSEWHERE. ANY FOG THAT
DOES DEVELOP WILL QUICKLY MIX OUT BY 13Z/9AM SUNDAY.
SHOULD SEE LESS IN THE WAY OF CU ON SUNDAY WITH REINFORCING DRY
AIR THAT WILL LIMIT ANY RETURN MOISTURE TO LATE IN THE DAY AND
MAINLY SW OF THE TAF SITES.
EXTENDED AVIATION FORECAST...
MOSTLY VFR OUTSIDE OF ANY CONVECTION THROUGH THE PERIOD. A FRONT
WILL SET UP IN THE MID ATLANTIC WHICH COULD BRING A FEW SHRA/TSRA
BY TUESDAY...WITH PERHAPS A BIT MORE COVERAGE LATER WEDNESDAY AT
THIS POINT. THUS THE THREAT OF SUB-VFR REMAINS LOW UNTIL AROUND
MIDWEEK...EXCEPT FOR THE TYPICAL FOG POTENTIAL AT KLWB/KBCB EACH
MORNING BETWEEN 09-13Z.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WP
NEAR TERM...JH/WP
SHORT TERM...NF
LONG TERM...WERT
AVIATION...JH/WP
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
323 PM CDT SAT AUG 1 2015
.SHORT TERM...
TONIGHT - CONFIDENCE...LOW
MAIN FOCUS WILL BE PINNING DOWN CONVECTIVE TRENDS AS THE NIGHT WEARS
ALONG. 850 LLJ BECOMES MORE FAVORABLE AIMING INTO CWA WITH INCREASING
WAA AND MOISTURE ADVECTION. MODELS ARE SHOWING VARYING SOLUTIONS FOR
MCS TRACK. 1000-500 MILLIBAR THICKNESS LINES/MCS MAINTENANCE
COMPOSITE INDEX FROM SPC MESO PAGE FAVOR MORE OF A 00Z ECMWF SOLUTION.
THE 12Z NAM IS THE FURTHEST NORTH WITH PRECIP INTO CNTRL/SRN WI. THE 12Z
ECMWF HAS COME MORE IN LINE WITH OTHER MODELS SHOWING CONVECTION
ARRIVING AFTER 6Z ACROSS THE CWA. GIVEN THE PROGGD ELEVATED
CAPE/CONSENSUS OF LLJ FORCING AND MID LEVEL SHORTWAVE WILL STILL
CARRY HIGH END CHANCE POPS FOR WHOLE CWA BUT WATCHING FOR A
POTENTIAL SE CURVE TO ANY MCS THAT MIGHT TAKE SHAPE THAT COULD LEAVE
PARTS OF SRN WI MORE ON THE NORTHERN FRINGE OF A SEWD DIVING MCS TRACK
FAVORING NE IA INTO NRN IL. WATCHING AFTERNOON VSBL ANIMATION THINKING
MORE LIKELY SCENARIO IS WE WILL BE SEEING OUR ACTIVITY ORIGINATE FROM
WRN MN INTO ERN ND WHICH WOULD FAVOR SRN WI A BIT MORE. OVERALL MODEL
SOLUTIONS INCLUDING LATEST HRRR FAVOR SOME CONVECTION A BIT LATER
IN THE NIGHT ACRS SRN WI HOWEVER THERE IS SOME LOSS TO THE
ORGANIZATION AND COVERAGE IN THE LATEST HRRR RUN. AND THIS REFLECTED IN
THE LATEST SWODY1 WITH THE REMOVAL OF THE SLIGHT RISK FROM SRN WI.
SUNDAY - CONFIDENCE...MEDIUM
COULD STILL BE DEALING WITH LINGERING MORNING CONVECTION
ASSOCIATED WITH THE LLJ/500 MILLIBAR SHORTWAVE. THEN WILL HAVE TO
SEE HOW THE MESOSCALE DETAILS PLAY OUT. EVEN THE GFS SOUNDING IS
GENERATED CAPES OVER 2K SUNDAY AFTERNOON. 850 JET IS PROGGD TO
FOCUS MORE TO OUR EAST AND SOUTHEAST AS THE DAY WEARS ON. HOWEVER
SURFACE/850 FRONT WILL STILL BE HANGING BACK TO THE NORTH AND A
WSW LOW LEVEL FLOW WILL REINFORCE MOISTURE INSTABILITY AS THE DAY
WEARS ON. CWASP SHOWING SOLID MID 70S PLUS ON ALL PROGS WITH THE
GFS SHOWING 80 PLUS BY 00Z. SO GIVEN PRONOUNCED LOW LEVEL FORCING
APPROACHING WITH SURFACE/850 FRONT SWODY2 SLIGHT IS WARRANTED WITH
THE GREATEST THREAT LATER IN THE AFTERNOON.
SUNDAY NIGHT... FORECAST CONFIDENCE MEDIUM.
SYNOPTIC AND MESOSCALE MODELS ARE IN FAIR AGREEMENT WITH
THUNDERSTORMS DEVELOPING ALONG THE COLD FRONT AS IT TRACKS FROM
CENTRAL WI DOWN THROUGH SOUTHEAST WI AND NORTHERN IL LATE SUNDAY
AFTERNOON THROUGH SUNDAY EVENING. I WENT WITH LIKELY POPS IN
SOUTHEAST WI SUNDAY EVENING... BUT IT MAY JUST BE A BROKEN LINE.
SHOWERS AND STORMS SHOULD WIND DOWN QUICKLY AFTER MIDNIGHT AS DRY
AIR SETTLES IN BEHIND THE FRONT.
EXPECTING HIGH CAPE AND SHEAR JUST AHEAD OF THE FRONT... ENOUGH TO
PRODUCE LARGE HAIL AND DAMAGING WINDS WITH ANY STRONG THUNDERSTORMS.
A TORNADO IS A REMOTE POSSIBILITY GIVEN THE LIMITED LOW LEVEL SHEAR.
.LONG TERM...
MONDAY THROUGH WEDNESDAY... FORECAST CONFIDENCE HIGH.
NORTHWEST FLOW WILL DOMINATE THE GREAT LAKES REGION FOR THE FIRST
PART OF THE WORK WEEK AS AN UPPER LOW REMAINS STATIONED OVER QUEBEC.
HIGH PRESSURE AT THE SURFACE WILL ALLOW FOR FAIRLY LIGHT WINDS.
TEMPS WILL BE AROUND SEASONAL NORMAL MONDAY AND TUESDAY... THEN
SLIGHTLY COOLER IN THE MID 70S WEDNESDAY DUE TO NORTHEAST BREEZE OFF
THE LAKE.
THURSDAY THROUGH SUNDAY... FORECAST CONFIDENCE MEDIUM.
MODELS TRY TO GENERATE AN MCS OVER THE NORTHERN PLAINS THAT TRACKS
SOUTHEAST THROUGH THE MIDWEST THURSDAY AND POSSIBLY ANOTHER ONE INTO
FRIDAY. THE GFS IS MAINTAINING PRECIP CHANCES IN SOUTHERN WI WITH
THIS SYSTEM AND APPEARS TO HAVE SOME CONVECTIVE FEEDBACK ISSUES...
WHILE THE 12Z ECMWF SHIFTED THE MAIN CHANCES FARTHER SOUTH.
EXPECT DRY HIGH PRESSURE TO SETTLE BACK INTO THE GREAT LAKES REGION
BY FRIDAY NIGHT AND KEEP PRECIP CHANCES MINIMAL THROUGH THE WEEKEND.
TEMPERATURES SHOULD BE IN THE 70S.
&&
.AVIATION/00Z TAFS/...VFR CONDITIONS AT LEAST INTO THIS EVENING.
MAIN FOCUS FOR CONVECTIVE DEVELOPMENT ARRIVES LATER TONIGHT INTO
SUNDAY MORNING AS MORE PRONOUNCED LLJ AIMS INTO SRN WI. STILL SOME
TRACK UNCERTAINTY ON MCS BUT OVERALL MOIST ADVECTION WITH 850 LLJ
AND SHORTWAVE ACTIVITY WARRANTS THE CHANCE OF STORMS LATER TONIGHT
INTO SUNDAY MORNING. POCKETS OF MVFR CIGS/VSBYS WITH ANY STRONGER
STORMS. MESOSCALE DETAILS AFTER OVERNIGHT/EARLY MORNING STORMS WILL
DICTATE STORM EVOLUTION/SEVERITY ON SUNDAY AFTERNOON/EVENING AS
SURFACE LOW AND COLD FRONT INTERACT WITH POTENTIALLY VERY UNSTABLE
AIRMASS. IN ADDITION WITH LOW LEVEL JET STRENGTHENING OVERNIGHT SOME
LOW LEVEL WIND SHEAR IS POSSIBLE.
&&
.MARINE...SMALL CRAFT ADVISORY HOISTED FOR SUNDAY AS PRESSURE
GRADIENT TIGHTENS UP AHEAD OF APPROACHING SURFACE LOW PRESSURE
SYSTEM. SW WINDS SHOULD RAMP UP PRETTY QUICK IN THE MORNING AND GET
RATHER GUSTY. COLD FRONT MAY SPAWN SOME STRONG TSTORMS LATE
AFTN/ERLY EVE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM 9 AM TO 6 PM CDT SUNDAY FOR LMZ643>646.
&&
$$
TONIGHT/SUNDAY AND AVIATION/MARINE...COLLAR
SUNDAY NIGHT THROUGH SATURDAY...MRC